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MORNING GLORY SCHOOL AND COLLEGE
SAVAR CANTONMENT
CLASS – IX, X
SUBJECT – PHYSICS
CREATIVE QUESTIONS Chapter -1
Physical Quantities and Measurement
1. The vernier constant of slide calliper is 0.01cm. The
diameter of a sphere is measured using this slide
callipers. Here the main scale reading is 12.2cm,
vernier coincidence is 5. There is no instrumental
error in this slide callipers. The mass of the given
sphere is 1 kg.
a. What is called least count?
b. Force is a derived quantity – Explain.
c. Determine the radius of the given sphere.
d. The sphere will whether sink or float in water
– Explain with mathematical logic.
Chapter – 2
Motion
1. A deer of mass 80 kg is running with uniform velocity
75kmh-1. In the meantime, a tiger of mass 200kg
which was hiding behind a tree started chasing the
deer from 75m behind with uniform acceleration
1.5ms-2 for 30s.
a. What is inertia?
b. What do you understand by 50N force?
c. Find the kinetic energy of the tiger after 10s.
d. Is it possible for the tiger to catch the deer? Give
your opinion with mathematical analysis.
2.
Velocity (ms-1) 0 10 20 30 40 50 60
Time (s) 0 4 8 12 16 20 24
a. What is called dimension?
b. Explain why the weight of a body varies at
different places of the earth.
c. Find out the distance travelled at 6th second in the
light of information of the stem.
d. Draw the graph in the light of given information
and find out the slope of the graph.
3.
A private car moves with a uniform velocity 21ms-1
from position P and a truck moves from rest with a
uniform acceleration 2ms-2 from position Q in the
same time and same direction.
a. What is called pitch?
b. Force is a derived quantity – Explain.
c. Determine the distance travelled by the truck in
20th second.
d. How many times will the private car and the truck
meet together? Explain with mathematical logic.
4. An object from rest travels the distance 50m in 5
seconds with uniform acceleration.
a. What is called acceleration?
b. Why is the acceleration of an object moving
uniformly zero?
c. What will be the velocity of the object after 15
seconds?
d. How long will the object take to travel the next
30m distance? Show it through mathematical
analysis.
5.
Fig: Three pieces of wood of different thickness: A,
B, C.
A bullet of mass 10 gm with a velocity 300ms-1
Penetrates one-third of the total thickness of three
pieces of wood A, B, C and after this its velocity
became half.
a. What is called gravitational force?
b. Why is frictional force produced?
c. Find out the value of the opposing force.
d. Can the bullet penetrate the rest of the thickness
of woods afterwards or not? Give your opinion
through mathematical analysis.
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6.
Figure: Momentum-time graph of a 10 kg object.
a. Write down the Law of conservation of
Momentum.
b. Explain why trees from outside of a moving bus
seem moving.
c. Determine the distance covered by the 1st object
in 25 second.
d. Mathematically compare the force acting on OA,
AB and CD.
7.
Time (s) 0 8 16 24 32 40 48
Velocity (ms-1) 0 4 8 8 8 4 0
The change of magnitude of velocity of different times for
a moving car from rest is shown in the given chart.
a. What is dimension?
b. What do you mean by instantaneous speed?
Explain.
c. Calculate the distance travelled by the car within
1st 32s?
d. According to given stem draw the graph and
explain the nature of velocity for different parts.
8. Starting from rest, the velocity of a train, moving with
uniform acceleration became 30ms-1 after 1 minute.
After that the train travelled 250m distance with
uniform velocity, then the driver used the brake and
before going to rest the train passed 125m distance
with uniform retardation.
a. What is displacement?
b. Why is the motion of simple pendulum
oscillatory?
c. Find the acceleration of the train at 1st minute.
d. Was the travelling time of the train with uniform
velocity as well as uniform retardation same or
different? Explain with mathematical logic.
9.
In the fig. a body ‘A’ is falling from a height 120m.
At the same time, another body ‘B’ is thrown
vertically upward with a velocity 19.6ms-1.
a. Define efficiency.
b. What is meant by the force of amount 6×105N?
c. Determine the velocity of ‘A’ body after 1.8s
d. Except for ground, will these bodies meet at any
point? State your opinion with a mathematical
explanation.
10. Sadek takes his motorcycle and with his friend Dipu
with a view to visiting their another friend. Their
motorcycle starting from rest and in 10s it attains a
velocity 72 kmh-1. Then it travels 2km with uniform
velocity.
a. What is displacement?
b. Write down two differences between velocity and
speed.
c. Determine the acceleration of Sadek’s
motorcycle.
d. If Sadek travels whole distance with half
acceleration instead of the mentioned
acceleration, then he reached earlier at the
destination – Analyze mathematically.
11.
A rat moves from B at a velocity of 0.4ms-1 to collect
a piece of bread. A cat noticed the rat from A and
moves in a forward direction in the same path with an
acceleration of 0.02 ms-2 to collect the bread.
a. What is fundamental quantity?
b. There is no change in acceleration without change
in velocity – Explain.
c. What velocity will be acquired by the cat at B?
d. Explain by mathematical explanation whether it is
possible for the rat to collect the bread before the
cat?
12. Two cars, each of similar mass, M, star their journey
at 6ms-1 and 9ms-1 and reach their destination. They
have an acceleration of 5ms-2 and 3ms-2 respectively.
a. What is electromagnetic force?
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b. Explain why the velocity of an object changes as
it falls downward from a state of rest.
c. At what time did the two cars reach their
destination?
d. Explain in terms of mathematical explanation, the
change in kinetic energy of the two cars.
13.
Time t (min) 0 5 10 15 20 25
Velocity, v(ms-1) 2 4 6 6 4 0
a. What is called vector quantity?
b. Will your weight be equal in all the countries of
the world? – Explain.
c. Find out the distance travelled in first 10 minutes
by the car.
d. Drawing the velocity-time graph from the above
table give your opinion about the velocity of the
car.
14. A bullet of 10 gm is shot from a pistol which mass is
2kg. The bullet moves at a velocity of 500ms-1 upon
release and the pistol moves backwards at a velocity
of 2.5ms-1. The time of contact was 0.1 sec.
a. What is fundamental quantity?
b. Why does an electronic fan rotate for some time
even after it is switched off? Explain
c. Determine the weight of the pistol.
d. Explain with which law of Newton is the above-
mentioned incident similar.
15. Rafique collected the velocity of his father’s car while
going to his school by looking at the speedometer
after every 10s and listed his recordings in the
following table.
Time t (sec) 0 10 20 30 40 50 60
Velocity, v(ms-1) 0 20 40 60 80 100 120
a. What is instantaneous speed?
b. What is a vibrating tuning fork’s speed called?
c. Draw a velocity vs time graph from Rafique’s
collection.
d. Determine the constant acceleration from the
graph- explain in terms of mathematical ideas.
16.
In the figure there showed the speed of a car with
300kg mass.
a. What is Retardation?
b. What do you mean by the acceleration of a body
is 10ms-2 towards the east?
c. Calculate the distance travelled of the first 15
second of the car.
d. Compare the highest and lowest kinetic energy of
the car.
17. The driver of a car moving with a velocity of 54
kmh-1 saw a pedestrian 46m away and immediately
applied the brake. The car stopped 1m in fornt of the
pedestrian.
a. What is fundamental quantity?
b. What will be shape of velocity versus time graph
of a particle moving with uniform acceleration in
straight line? Draw the curve.
c. Find the time required to stop after applying the
brake.
d. What should be the speed of car to stop this car
just in front of the pedestrian?- Analyze
mathematically.
Chapters – 3
Force 1.
a. Write down the Third law for a free-falling object.
b. Explain why an electric fan does not stop rotating
right after the switch is turned off?
c. Determine F.
d. If after the object crosses 100m the applied force
is removed, determine the total time it needs to
stop. Explain mathematically.
2.
There is a collision between two cars P and Q after
running a distance, as a result, the combiner car
moves together with a velocity 2ms-1 toward Q.
a. What is called balanced force?
b. Explain the effect of force on the shape of a body.
c. At what time will the car P and Q meet together?
d. The incidence supports the law of conservation of
momentum but not the Kinetic energy – Explain
with mathematical logic.
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3. Due to applying force upon a toy car of weight 3.92N,
it starts to move with an acceleration 0.5ms-2 on the
floor where frictional force is 0.5N.
a. What is acceleration due to gravity?
b. The weight of anybody is zero at the center of the
earth- Explain.
c. Calculate the force acting upon the car.
d. Will you get any change in acceleration due to the
frictional & frictionless floor? Evaluate
mathematically.
4. A cricket ball is thrown vertically upward by Mukul
with an initial velocity 20ms-1. At the same time,
Nishan tried to catch the ball coming with a uniform
velocity of 6ms-1 from 30m away.
a. What is called pitch?
b. Power is a derived quantity- Explain.
c. Find out maximum height of the ball.
d. Is it possible for Nishan to catch the ball before
dropped on earth? Give your opinion with
mathematical analysis.
5. A truck of mass 600 kg starts from rest moving with
uniform acceleration 0.2ms-2, after 60s collides with a
stationary pick-up van of mass 400kg gets locked
with it and moves together with velocity 7.2 ms-1.
a. What is sliding friction?
b. Write two differences between balanced and
unbalanced forces.
c. On the basis of the above stem how far distance
the truck will cover before collision with the pick-
up van?
d. Does the above phenomenon support the principle
of conservation of momentum? Given your
opinion.
6. A bullet of mass 10g shoot from a gun with a velocity
of 600ms-1. In this time it exerts backward velocity of
2ms-1.
a. What is the least count?
b. What do you mean by least count of screw gauge
is 0.01mm?
c. Determine the mass of the gun.
d. How can you decrease the value of the backward
velocity of the gun? Explain probable ways with
mathematical logic.
7.
a. What is frequency?
b. Explain at which point of the earth, the value of
‘g’ is highest.
c. Determine at what velocity the object will hit the
earth.
d. Explain using mathematical explanation, there
will be a change in potential energy and kinetic
energy of the object upon moving from A to B.
8. Tanjum throws a stone of mass 50g horizontally with
a velocity of 60ms-1
a. What is called dimension?
b. What do you mean by the force 10N?
c. Calculate the distance travelled by the stone in 4s,
if the stone moves with uniform velocity.
d. Is it possible to stop the stone in 10m by applying
an opposite force of 9N? Give your opinion with
mathematical analysis.
9. A foundation of height is 50m. A body of mass 20kg
is moving with the velocity of 5ms-1 from position A.
By applying force towards velocity, its velocity
becomes 30ms-1 after 5 sec at position B.
a. What is called balanced force?
b. Will you get work at all time if force is applied on
a body- Explain.
c. Find the applied force on the body.
d. Will be any discrimination of total energy of the
body at position A and B? Give your opinion by
mathematical analysis.
10. A hunter throws a bullet to target a bird with velocity
400ms-1 from a gun of mass 2kg. The bullet missed
the target to enter a tree of 4.5cm and stopped. The
mass of bullet was 10g.
a. What is wave?
b. Find the relation, force, mass and acceleration.
c. Determine the Backward velocity of the gun.
d. Determine the magnitude of opposing force on
the bullet and how much time was spent for
crossing that distance.
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11. Buses A and B of masses 1000kg and 1200kg move
with 30m/s and 25m/s respectively in the same
direction. They collide due to fog. Bus B moves with
5m/s after collision.
a. Define momentum.
b. Write down the advantages of friction.
c. Calculate the velocity of bus A.
d. The less the time of collision the more is the
magnitude of force. Explain mathematically.
12. An elastic collision is occurring in the following
incident.
a. Write down the conservation law of momentum.
b. What is the change of momentum of the object of
10kg?
c. Find out the velocity of the object of 5kg after a
collision along with its direction which it will
move.
d. If the time of collision is 0.1 sec. Does the above
incident follow Newton’s third law of motion?
13. A truck of 2000kg is moving with a velocity of
54kmh-1 and collide with a bus of 800 kg of velocity
45kmh-1 coming from opposite side. After collision
they stuck together and started to move combinedly.
a. Define force
b. Show that, impulse of force equal to change of
momentum.
c. Determine the kinetic energy of the truck before
collision.
d. Does the phenomenon support the conservation
law of momentum? Analyze mathematically.
14. A bullet of mass 10gm is shot from a gun with a
velocity of 1kms-1. The bullet stops after penetrating
3cm of a wood.
a. What is called half life?
b. Write the Snell’s law and explain.
c. If the mass of gun is 50kg, what will be the
backward velocity of the gun?
d. Determine the resistive force of the bullet in the
light of the stem.
15. A hammer of mass 25 kg falls on a pile from a height
of 15m and comes to rest in 0.1 sec.
a. What is the impulse of force?
b. From the idea of impulse of force prove the
principle of conservation of momentum.
c. What will be the velocity of the hammer when it
will touch the pile?
d. What force acts on the pile?
16. A bullet of mass 10g was fired from an efficient
hunter’s gun of 6kg mass at velocity of 300ms-1 and
during firing backward reaction of gun was created.
a. What is momentum?
b. Explain how the concept of inertia is obtained
from Newton’s first law of motion.
c. Calculate the backward velocity of the gun.
d. Does this event obey the conservation principle of
momentum? Explain with mathematical Analysis.
Chapter – 4
Work, Power and Energy
1.
a. What is kinetic energy?
b. When we throw an arrow by stretching the string
of a bow, how does the energy transformation
take place?
c. Determine at which velocity the object will hit the
ground?
d. If the object is dropped freely from the point B,
the object follows the conservation of energy.-
Explain mathematically.
2.
The body is dropped from the position A freely.
a. What is called potential energy?
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b. Explain why biomass can be considered as a
multiple source of energy.
c. If the time to lift the body at position A from the
ground be 2 minutes, what power is used?
d. Does the law of conservation of energy follow at
position B and C in above stem? Evaluate
mathematically.
3. A toy car of mass 250gm is generated by an engine of
5J energy, at 1st trail its continues with 4ms-1 uniform
velocity and in the 2nd trail it starts from rest with
uniform acceleration 1 ms -2 and travels 8m distance.
a. What is 1 Joule?
b. Why is it difficult to open a water tap having a
screw like turns with wet soapy hand? Explain.
c. Determine the required time to travel the distance
in the 2nd trail mentioned in the above stem.
d. Is there any change of efficiency of the toy car in
both trails? Explain with mathematical logic.
4. Rony lifted up a flag of mass 200gm applying IN
force at a height of 10 m which was tied with a string
with the help of a pulley. Secondly, he released an
object of mass 1 kg tieing it at the other end of the
string from a height of 2m and succeeded to lift up the
flag at the same height. Rony takes 5 second to lift up
the flag.
a. What is uniform acceleration?
b. What will be the graph of uniform acceleration in
(v-t) graph? Explain.
c. Determine the power of Rony to lift up the flag.
d. Will the 2nd process follow the law of
conservation of energy? Explain mathematically.
5.
A body of mass 100g is static at a point A. The body
is released from that point.
a. Write down Newton's second law of motion.
b. Why does a screw get stagnated with a wall when
it is penetrated into the wall? Explain.
c. Determine the maximum Kinetic Energy of the
body.
d. The total energy of the body at point A and B
remains the same -Explain with mathematical
logic.
6. A motor of 15kw can lift 2 quintal water in 1 minute
at a height of 300m.
a. What is called scientific symbol?
b. Write down two differences between linear
motion and rotational motion.
c. What is the effective power of the motor?
d. What will be the change in energy spent by the
motor if the efficiency is increased by 5%?
Analyze mathematically.
7. Kinetic energy is a kind of mechanical energy. The
mass of Rahim is 30kg and of Karim is 20 kg. Rahim
runs with a velocity 5ms-1 and Karim with a velocity
6ms-1. Total work done by them to get this velocity is
kinetic energy.
a. Write down Newton’s second Law.
b. Can the kinetic energy of Rahim be negative?
c. Whose kinetic energy was less? Calculate it.
d. If the momentum of Rahim and Karim is same
then whose kinetic energy will be more
relatively?
8. An engine of 1.5 H.P can fill up a tank of height 20m
within 30 minutes. The capacity of the tank is 2,000
liter. Another engine of 2 H.P can lift 3000 kg bricks
at the same height within 25 minutes.
a. What is stress?
b. What do you mean by potential energy? Explain.
c. Calculate the work done by the 1st engine.
d. Mathematically analyze the ratio of efficiency for
both the engines.
9.
In Figure, The body is falling from 'A' towards
ground.
a. What is called efficiency?
b. What factors does potential energy depend on?
Explain.
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c. How long will the body take to reach at 'C' from
'A'?
d. "The total energy of the body at point A and C are
unchangeable" verify this statement
mathematically.
10. Mass of Jony and Rony are respectively 40 kg and 50
kg. Jony and Rony can stair up 20 steps of 20 cm
height each in 10s and 18s respectively. [Acceleration
due to gravity is 9.8ms-2]
a. What is efficiency?
b. 'Searching alternative fuel of fossil fuel is very
important. -Explain.
c. Calculate work done by Jony.
d. Though Rony's work is more but Jony is ahead in
power. Evaluate the statement.
11.
a. What is called work done?
b. What is meant by the work done against the
force?
c. The object is allowed to fall freely from point A,
then what is the velocity at point C?
d. What is the height from the earth's surface where
the potential energy is equal to the kinetic energy-
-Give your opinion with mathematical analysis.
12. An electric motor of power 15 kW can lift 1000 kg
water on a roof of height 300 m in 0.5 minute.
a. What is called potential energy?
b. Distinguish between transverse wave and
longitudinal wave.
c. Calculate the efficiency of the motor.
d. Analyze mathematically the amount of energy used
by the motor within that time if the efficiency is
75%.
13.
While loading 10 nos. cement bag to a cargo lift of a
building of 60m height, at a height of 60m the steel
cable of cargo lift snapped resulting free fall of cargo
lift. Mass of cargo lift alone is 50 kg.
a. Define kinetic energy.
b. In all respect, equal work cannot be done by
applying force-- Explain.
c. On the basis of the above stem, calculate total
energy at point B when the total mass of cargo lift
with cement is 550 kg.
d. At point B if 2 nos. cement bag are accidentally
separated from cargo lift what percentage change
of total energy at point B will occur? Explain with
mathematical analysis.
14. Observe the following figure:
a. What is weightlessness?
b. Explain the relation between force and
acceleration.
c. Calculate the vertical height where the kinetic
energy will be doubled of the potential energy of
the object.
d. With the help of the figure, show that total energy
is conserved at the point A, B and C.
15. A boy throws a brick at a velocity of 12ms-1 at
0.25kg mango, which is 10m high from the ground to
dislocate it from its place.
a. What is friction?
b. What is Inertia? Explain.
c. Determine the Potential Energy of the mango in
its hanging state.
d. In terms of mathematical reasoning explanation,
explain whether it will be possible for the boy to
dislocate the mango or not.
16. An electric motor of power 2kW can fill an empty
water tank of capacity 1000 kg at a height of 10
meters in 2 minutes. On the other hand, another water
tank of power 5kW of capacity 1500kg at a height of
15 meters can fill water in the same time.
a. What is called force?
b. Whose inertia is more and why between a
microbus and a truck?
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c. Find out the potential energy of the water tank of
height 10 meter.
d. Which motor will be more beneficial?-Give your
opinion with mathematical argument.
17. A pump is used to raise 1500 liters of water per
minute from a 100m deep well. The efficiency of the
pump is 70%
a. What is Buoyancy?
b. Explain why an object floats or sinks.
c. Determine the efficiency of the pump.
d. Mathematically represent the amount of extra
time required to raise 1500 liters of water if the
efficiency of the pump is 60%
Chapter – 5
Pressure and States of Matter
1. The weight of an object of area 20cm2 and height
10cm in air and water is 9.8N and 7.84N respectively.
Here g = 9.8ms-2
a. State Archimedes’ Law
b. Write down the conditions of flotation and
immersion of a body.
c. Calculate the density of the material of the object.
d. Does the stem follow Archimedes’ law? Give
mathematical explanation.
2. The weight of a body of volume 400cm3 in the air is
19.6N. If it is immersed in water, its weight becomes
15.68N. At experimental place acceleration due to
gravity g = 9.8ms-2.
a. What is called buoyancy?
b. At definite depth, the pressure depends on the
nature of liquid. Explain it.
c. Find out the density of the body of the stem.
d. Does the above stem support Archimedes’
Principle? Give opinion through mathematical
analysis.
3. A water vessel of mass 300kg having volume 900 m3
floats on water, while 2.94×106N buoyancy acts on it.
It is tried to use the water vessel as a completely
immersed submarine by keeping its shape unchanged.
a. What is buoyancy?
b. What is the reason of variation of the pressure at a
point in a specific liquid at a fixed depth?
c. How many portions of volume of the water vessel
is immersed, when it floats on water?
d. To succeed in the last step what kind of change
should be taken? Explain with mathematical
logic.
4. The area of the lower part of a rectangular block is
25cm2. It is sunk into water. The density of water is
1000 kgm-3. The height of the upper surface of the
block from the upper surface of water is 5cm. The
height of block is 5cm.
a. What is density?
b. What is cause of floating and sinking of a solid
body? Explain.
c. Find out the pressure at the lower surface of the
block.
d. Does it follow the Archimedes’ Principle?
Analyze.
5.
a. What is called potential energy?
b. What is Torricelli’s Vacuum? Explain.
c. Find out the experienced force on the piston-2.
d. If the object A is released in the liquid of the
stem, will it float or immerse? Analyze
mathematically.
6. A pot is filled with water and another one is filled
with kerosene. First pot’s height is 75 cm and water
and kerosene has a density of 1000kg m-3 and 800 kg
m-3 respectively. There is another object whose
volume is 400 cm3.
a. Write down Hooke’s Law.
b. Why an embankment dam’s lower part is kept
wider than the upper part?
c. Determine the pressure working on the bottom
surface of the first pot.
d. If the object is drowned in 1st and 2nd pot, in
which pot buoyancy will be greater than the
other?
7. In a copper pot of 23°C temperature and 500g mass,
200 mL water of 75° temperature is kept. Due to the
exchange of heat, the final temperature is 65°C. As
water gave away heat, its apparent expansion is
1.49mL. (Here, is no other way heat was exchanged).
Copper’s coefficient of volume expansion is
50.1×10-6K-1. Water density is 1000 kgm-3.
a. What is density?
b. Why do we feel that an object lost its weight
when it is drowned in liquid?
c. Determine water’s real expansion.
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d. In the case above, to increase final temperature
5°C more, determine the quantity of extra water
that is needed.
8. An engine can lift 2000 liter water at the roof of a
building of height 18m in 1 minute. The efficiency of
the engine is 70%.
a. Write down Pascal’s law.
b. The potential energy of a body is 60J- What does
it means?
c. Determine the power of the engine.
d. What times more time is required to lift the same
water at the same height if the efficiency of the
engine is 60%?
9. Observe the figure below –
a. What is strain?
b. What do you mean by Torricelli’s vacuum?
c. Calculate the pressure on the PQ surface.
d. Is the information given in the stem supporting
Archimedes Law? Analyze Mathematically.
10. Mina sat with her little brother beside the pond. Her
brother hold a ball of mass 200g and of volume
250cm3. Suddenly the ball fell down into the pond.
The depth of the pond was 3m. (Density of water is
1000kg/m3 and g= 9.8ms-2).
a. State the law of Elasticity of Robert Hook.
b. What is meant by the work done 250J?
c. Determine the pressure of water at the bottom of
the pond.
d. Will the ball sink into the water? – Explain your
opinion mathematically.
11.
The radius of cylinder ABCD is 5cm.
a. What is called the apparent expansion of liquid?
b. Why do we not feel the atmospheric pressure?
Explain it.
c. Determine the pressure of the liquid at point C in
stem.
d. The weight of displaced liquid by the cylinder is
equal to the upward resulting force acting on the
cylinder. Prove this in light of the given
information of above stem.
12. A body of mass 2.5kg having length, breadth and
height 25cm, 15cm and 5cm respectively.
a. State Hooke’s Law.
b. Why the atmospheric pressure changes with the
changes of altitude?
c. Object of the above stem when placed on the
floor, calculate the highest and lowest magnitude
of pressure that will exert on the floor.
d. The object of the stem is placed in water of 4° C,
whether it will float of immersed in the water?
Explain with mathematical analysis.
13. Observe the figure-
a. Write Archimedes law.
b. Why is a heavy weight easy to lift in water?
Explain.
c. If a mass of 10kg is exerted on small piston then
what will be the upward force on large piston?
d. If a mass of 100 kg is exerted on large piston, is it
possible to stop upward lifting? Explain
mathematically.
14. Volume of a sphere (insoluble in liquid) is 1000cm3.
It floats being fully immersed in a liquid of density
1500kg m-3. The sphere is covered with wax of
volume 100cm3 of mass 80gm.
a. What is the unit of work?
b. Why does the iron sink in water but float on
mercury? Explain.
c. Calculate the mass of the sphere in the stem.
d. Whether the sphere covered with wax floats or
sink in the liquid? Give your opinion with
mathematical logic.
15. A pot of base area of 400cm2 is sunk into water.
Depth between upper surface of water and upper
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surface of the pot is 15 cm. The height of the pot is 90
cm and the mass of water with pot is 36.5kg.
a. What is stress?
b. Why are elasticity of all metals not same?
c. What is the applied force on the base area of the
pot?
d. If the pot is filled with sea water then its mass
becomes 36.6kg, then what type of situation the
pot will be in sea water? Give your opinion by
mathematical analysis.
16. The area of a body is 300 cm2. Its height is 0.1m and
mass is 5.5kg. The body was immersed in water. The
density of the water is 1000kgm-3.
a. What is strain?
b. Explain the reasons for floatation and immersion
of a body.
c. How much is the weight of the body is water?
d. How much volume is needed equal to the mass of
the body, when the body will be immersed fully
in water?
Chapter – 6
Effect of Heat on Substances
1. The depth of a well is 3500 cm, air temperature is
60°F. At this temperature, the velocity of sound is
343ms-1.
a. What is wave velocity?
b. Set the relationship between frequency and time
period.
c. What is the temperature of that place in Celsius
scale?
d. If any sound is produced at the mouth of the well
will echo be heard? Explain mathematically.
2.
The surface area of the figure is increased by 0.1m2
for the rise of temperature 30°C.
a. What is regelation?
b. Explain the plasma state of matter.
c. Find out the coefficient of linear expansion of the
metal piece.
d. What will be the increase in temperature to
increase the surface area of that metal 6%?
3. 24000J heat is applied to increase the temperature of a
rod of length 1m having mass 3kg from 30°C to 50°C,
whose expansion of length is 2.34×10-4m. The
expansion of the length of another similar rod is
2.2×10-4m for the same change of temperature.
a. What is the unit of thermal capacity?
b. Explain the effect of pressure on the melting
point.
c. Find the specific heat of the 1st rod.
d. What is the reason for the different value of linear
expansion of these two rods? Explain with
mathematical logic.
4. The temperature of the copper wire is increased by
150°C.
a. What is called triple point of water?
b. Pressure is a thermometric property of matter-
Explain.
c. Determine the required amount of heat applied to
the copper wire.
d. Will the copper wire be made to penetrate after
applying heat through a ring of diameter 10.06
mm? Explain with mathematical logic.
5.
a. What is called 1 Kelvin?
b. Why is air of fan felt cold in the sweating body?
Explain.
c. Find out the value of the temperature of the object
B in Fahrenheit scale.
d. What is the amount of heat needed to increase the
temperature of only liquid of the container A and
object B through 30°C separately? Which one
needs more and how much? Analyse
mathematically, (At 4°C, the mass of 1c.c water is
1gm)
6.
P a g e | 11
a. What is called specific heat?
b. Iron rod is used to build house – Explain.
c. Determine the mass of the sphere.
d. Will the body be lifted by applying 15N force in
the smaller piston? Explain with mathematical
logic.
7. Area of a copper plate and a steel plate at 10°C is 9m2
each. After applying heat, temperature becomes 50°C
and due to this the area of steel body becomes
9.012024m2.(Co-efficient of superficial expansion of
copper is 22.0×10-6K-1)
a. Define 1 Kelvin.
b. The rotation of the earth around the sun is which
type of motion? Explain.
c. Determine the coefficient of volume expansion of
copper.
d. By increasing the temperature is it possible to
place copper plate on the steel plate equally?
Explain your opinion mathematically.
8. In a factory, 1, 2 and 3 No. Level are attached to the
three lead plate respectively. The surface area of
every plate is 4m2. When No.1 plate is heated to the
temperature 175°C its surface area becomes 4.033m2.
No.2 and No.3 plates are heated to the temperature up
to 150°C and 170°C respectively [Room Temperature
25°C]
a. Define Evaporation.
b. If a big container and a small container have same
height and to keep same amount of water in the
two containers, then the evaporation of water will
be occurred of which container faster and why?
c. Determine the value of the coefficient of surface
expansion of No.1 plate.
d. The change of surface are of No.2 and No.3 plate
is not equal due to application of heat – Analyze
mathematically.
9. The length of a copper wire is 100 m at 25°C. Due to
the increase of temperature its length became
100.02m. The coefficient of linear expansion of the
wire is 16.7×10-6K-1.
a. What is specific heat?
b. Why thermal expansion occurs due to increase of
temperature?
c. What was the increase of temperature of that
wire?
d. If the wire was made by Aluminium and if 875°C
is needed to 100.02m length of the wire then
could you determine the coefficient of volume
expansion of Aluminium? Explain
mathematically.
10.
a. What is the plasma state of matter?
b. What is meant by the relative temperature of
copper is 400 Jkg-1K-1?
c. What is the temperature of the liquid in the 1st
container, according to the Kelvin scale?
d. Analyze what will happen to the movement of
heat if the temperature of the liquid in the second
container is increased by 10°F and the two liquids
are brought in contact with each other.
11. A 200m length of steel copper is used in a rail line.
There is a gap of 4 cm between two copper bars and
the temperature rises by 10°C. The linear expansion
coefficient is 11.5×10-6K-1.
a. Write Hooke’s law.
b. If an egg is released in a container filled with
water, it will sink. However, upon adding the
required amount of salt of the water the egg will
float. Explain.
c. Determine the expansion of length of the steel
copper.
d. Explain using mathematical explanation, The
effect on the rail line if the temperature is
increased by 15°C .
12.
A sound made from A can be heard from the point B.
a. What is speed?
b. Explain what kind of wave is a water wave?
c. Determine the velocity of sound according to the
mentioned temperature.
d. Explain using mathematical explanation whether
the mentioned echo can be heard from B.
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13. 420g of copper at 100°C is dropped in 200g of water
at 40°C. The temperate of the mixture is 50°C. The
specific heat of copper and water are 400Jkg-1K-1 and
4200Jkg-1K-1 respectively.
a. What is heat?
b. What is meant by the conductivity of lead is
35Wm-1K-1?
c. Determine the heat limit/ thermal capacity/ heat
capacity of copper.
d. Explain using mathematical explanation, how the
mentioned action agrees with the basic principles
of calorimetry.
14. The length of an iron rod is 2m. Its temperature raised
through 10°C so that a small amount of length
increase. The coefficient of linear expansion of iron
and copper are 11.6×10-6K-1 & 16.7×10-6K-1
respectively.
a. What is evaporation?
b. Specific heat of silver is 230Jkg-1K-1. What does it
mean?
c. What would be the reading in Fahrenheit scale of
the increased temperature?
d. Will the linear expansion be same if the rod is
made up of copper instead of iron? Explain with
mathematical logic.
15. By applying 1950J heat upon a wire of mass 0.5kg,
its temperature is raised 30K and final length becomes
100.033 m.
a. What is called vernier constant?
b. It is possible to boil water at 371K. Explain.
c. Determine specific heat of the material of the
wire.
d. It is possible to enter a ring made by the initial
length of the wire inside a hollow cube of height
32m? Give your opinion with mathematical
analysis.
Chapter – 7
Wave and Sound
1. The frequencies of sounds produced from two
different sources in medium P are 340Hz and 400 Hz
and the difference of their wavelengths is 0.165m. In
another medium Q the velocity of sound is 400ms-1.
a. What is called contact force?
b. Explain the relation between the velocity of sound
with the nature of medium.
c. Find out the velocity of sound in medium P?
d. If the difference of wavelength of same sound in
both media is 0.1m, then will the wave travel the
distance 124 m in medium Q by 80 complete
vibrations? Give opinion through Mathematical
analysis.
2. The frequency of a sound wave produced by a source
is 86Hz whose speed is different in water and air.
Speed of this wave in water is 1450ms-1 and the figure
of vibration in air is given below –
a. What is phase?
b. What is meant by intensity of sound 25Wm-2-?
c. Find the time period of the wave in water?
d. Why the speed of the sound wave is different in
those two mediums mentioned in the stem?
Explain mathematically.
3. A person standing between two ten storied buildings
shot a bullet from a gun He heard the first echo after
2s and second echo after 2.15s. The temperature of air
was 35°C at that time.
a. What is called amplitude?
b. The intensity of sound is 40 Wm-2 – what does it
mean?
c. Determine the distance between the buildings.
d. At what time after hearing the second echo, he
will hear the third echo? Explain with
mathematical logic.
4. Palash makes a sound in front of a hill. After 0.15s he
heard an echo. The temperature of air was 30°C.
a. What is wave?
b. Why can all reflected sound not be heard?
c. What was the distance between Palash and the
hill?
d. If palash continues to move towards the hill then
what will be the maximum distance he heard the
echo? Analyze mathematically.
5.
a. What is echo?
b. Why is the velocity of sound more during daytime
than night?
c. Find out the distance between the position M and
reflector R.
P a g e | 13
d. If sound is produced at position T, will echo be
heard? If echo is heard, then after how long will
echo be heard? Give your opinion through
mathematical analysis.
6. The velocity of sound in air is 347ms-1 and in water
1474.75ms-1.
a. What is called amplitude?
b. A sweating person feels cool under a running fan
– Explain why.
c. Determine the temperature of air.
d. What will be the change of wavelength of sound
in water in compare with air? Explain with
mathematical logic.
7. A radio station broadcasts folk song in every morning
10am with frequency 350 kHz. Radio wave velocity is
3×108ms-1. Wavelength of another wave created in
water is one percent of radio wave. The velocity of
sound in water is 1450 ms-1.
a. What is frequency?
b. Male voice is harsh but child and female voice is
shrill. Explain.
c. Calculate the wavelength of radio wave.
d. Frequency of radio wave, how many times of that
of wave created in water? Analyze
mathematically.
8. The frequency of Anika’s vocal cord is 700 Hz. She
calles a boatman who stays at the middle of river.
Anika hears echo of her created sound due to the
reflection from the other side of the river after 1.6
second. The velocity of sound of that time is 350ms-1.
a. What is called phase?
b. Why is the voice of women sharp whereas that of
adult men is deep? Explain.
c. Calculate the wavelength of the sound created by
Anika.
d. Will the boatman hear the echo of the sound of
Anika? Give your opinion with mathematical
analysis.
9. A man fired from a gun standing between two parallel
hills. He got two echoes after 1.5 s and 2s later from
firing. That day the temperature was 30°C.
a. What is echo?
b. Velocity of sound in water is more than that in air
medium. Explain.
c. Calculate the distance between the mentioned
hills.
d. Will the man be able to hear 3rd and 4th echo
separately? Analyze mathematically.
10.
The time taken to reach A to B for 1st wave and C to D for
2nd wave are respectively 0.05s and 0.08s. Velocity of 1st
wave is 300ms-1.
a. Define the range of audibility.
b. “Whenever a sound is created at one end of a long
hollow steel pipe, then at the other end, the sound
is heard two times.” – Explain why?
c. Determine the displacement after 10sec for 1st
wave.
d. Compare the frequencies of the above given two
wave.
11.
a. What is called echo?
b. Explain the role of friction in the smoothness of
road.
c. Find out the distance between S and R.
d. Is it possible to hear the echo at position P? Give
opinion with mathematical analysis.
12. Standing 17m away from a hill, Kajol could not hear
any echoes despite making a loud sound. He moved
further back and was able to hear the echoes. The
velocity at that place was 35ms-1 and the frequency of
the sound was 1400Hz.
a. What is frequency?
b. Why do bats feel more comfortable at night?
Explain.
c. Determine the wavelength of the above
mentioned sound.
P a g e | 14
d. Explain using mathematical explanation, why
Kajol did not hear the echo in the first
place/Position?
13.
In the picture, a wave created in water is shown. The
speed of sound wave in air and water is 332 ms-1 and
1452.5 ms-1.
a. What is Harmonic motion?
b. Explain why females have a higher voice pitch
than males.
c. From the given diagram determine the
wavelength of the wave in air.
d. Explain using mathematical explanation, what
will be the time required to listen to the echo in
the well if the depth of the well is equal to the
length of the sound wave in air.
14. A man makes a sound loudly standing at a distance of
17 meters from a hill when he went to visit Sylhet to
listen to echo. The velocity of that sound was 350m/s
and the wavelength was 20cm.
a. What is called periodic motion?
b. How the sound transmits to other when we talk?
c. Find out the frequency of that sound.
d. Can the man listen to the echo? Give your opinion
with a mathematical argument.
15.
a. What is called wave velocity?
b. What is the type of wave in the stem? Explain.
c. Calculate the frequency of the wave.
d. Is there any change of frequency if the
wavelength made half keeping the amplitude
constant? Analyze mathematically.
16. After shooting a bullet from his pistol, Babloo
standing 2301m away from a nearby land beside a hill
started running towards the hill. He heard the echo 3
seconds after shooting. The temperature of the air was
25° C that day.
a. What is periodical speed?
b. Write down two differences between latitudinal
and longitudinal wave.
c. What was the velocity of sound in air during that
time?
d. Give a mathematical explanation of Babloo’s
measurement of velocity.
17.
a. What is called musical sound?
b. Why definite distance is necessary to hear an
echo?
c. Determine the frequency of sound in air medium.
d. If the medium is metallic of stem, then will be
possible to hear sound in the same time.
18.
a. What is complete vibration?
b. Frequency is the inverse proportion of time
period- Explain it.
c. How much minimum distance between P and AB
will be needed to hear echo? Calculate it.
d. Will the echo be heard or not if being produced
from P and reflected by AB, the sound producing
incident takes place in water instead of air?
Analyze it mathematically.
Chapter -8
Reflection of Light
1. A dentist uses a spherical mirror ‘X’ of focal length
6cm. And a driver uses another spherical mirror ‘Y’
of focal length 60cm where the distance of the image
of another car is – 50cm.
a. What is optical center?
b. What is meant by power of lens – 0.25D?
c. What was distance of the car is seen in the mirror
‘Y’?
d. If the dentist placed the mirror ‘X’ at 4cm and
8cm away from teeth then which position of the
P a g e | 15
mirror will be more effective? Explain with the
help of ray diagram.
2.
a. What is called optical fiber?
b. Refractive index of water respect to air is 1.33 –
what does it mean?
c. If a body is placed 30 cm away from the mirror,
determine the distance of the image.
d. At what place should an object be placed to form
real and magnified image? Explain with ray
diagram.
3.
a. What is lens?
b. Explain why concave lens is known as diverging
lens?
c. What will be the position, nature and size of
image for the given object? Explain with suitable
ray diagram.
d. Is it possible to get virtual image from the given
mirror? Analyze with ray diagram.
4.
a. What is called pole of a mirror?
b. Why is concave mirror called converging mirror?
Explain.
c. Calculate the linear magnification if an object is
placed at 24 cm apart from the mirror on its
principal axis in figure.
d. In figure, if two objects are placed at 10 cm and
15 cm in front of the mirror then explain the
position and nature of their images with ray
diagram.
5.
The refractive index of a in relation to b is 1.5. The
velocity of light in medium a is 3×108ms-1.
a. What is Reflection of light?
b. Why do the perpendicular rays return in the same
path as it falls?
c. Determine the velocity of light in medium b.
d. Will the rays of AB and CD be parallel to each
other? Explain in terms of mathematical
explanation.
6. Observe the figure and answer the following
questions.
a. What is total internal reflection of light?
b. If the focal length of a lens is -0.1m, then what is
the power & name of the lens?
c. Find the nature and position of the image of the
above figure.
d. If this object is at C then what will be the
position, size & nature of the image?
7.
a. What is optical fiber?
P a g e | 16
b. What happens to the beam of rays entering a
concave lens?
c. Find out the power of above lens.
d. Do you get the virtual and erect image of the
object from the above figure? Analyze it by
drawing ray diagram.
8. An object is placed 30cm away from a concave mirror
of focal length 40cm.
a. Define total internal reflection.
b. What do you mean by critical angle of Kerosin
44° with respect to air?
c. At what distance the image was formed from the
mirror?
d. Sketch a ray diagram and explain the formation of
image according to the stem.
9.
Name of the person Near point Far point
Jack 1m -
Jill - 80cm
a. Define magnification.
b. Why do we prefer a convex mirror as a rear-view
mirror in vehicles?
c. Find out the focal length of the lens required for
Jill.
d. Make a diagram to show how the defect of Jack is
corrected? And what type of lens is used for this?
Comment through mathematical analysis.
10. The near points and far points of defective eyes of
two persons “Ali” and “Belal” are shown in the table
below:
Name of the person Near point Far point
Ali 15cm 100 cm
Belal 35cm Infinity
a. What is optical center?
b. What do you mean by Refractive index of glass
with respect to air is 1.52?
c. Calculate the power of lens of the spectacles of
‘Ali’.
d. How image of the lens of spectacles of Belal was
formed? – Explain with ray diagram.
Chapter – 9
Reflection of Light
1.
a. What is reflection of light?
b. When will total internal reflection take place?
Explain.
c. Calculate the velocity of light in ‘b’ medium.
d. If air medium in the stem is replaced with
glass medium, is it possible to find total
internal reflection? Analyze drawing required
figure.
2.
The velocity of light decreased by one-third as light
entered into medium b from medium a. Velocity of
light in medium a is 3×108ms-1.
a. What is called refractive index?
b. Explain the advantage of having two eyes.
c. Find out the value of incident angle if the
angle of refraction is 35°.
d. If the angle of refraction is increased by 5°
without changing the value of incident angle,
what will be the change of the velocity of
light in medium b? Give opinion with
mathematical logic.
3. A body is placed on the principal axis at a distance 20
cm of a lens of power+2.5d.
a. What is called radioactivity?
b. A normal eye can see an object of any
distance- Explain.
c. Determine the distance of the image of the
object.
d. Which defect can be rectified with the help of
the given lens? Explain with ray diagram.
4.
P a g e | 17
a. What is called optical center of a lens?
b. Explain the accommodation of eye.
c. Find the power of lens in figure 1.
d. How will be the image if the object is kept at
A and B in figure 2? Analyze with ray
diagram.
5.
a. Write down the Snell’s Law.
b. Explain perceptions of coloured object.
c. What will be the velocity of light in glass?
d. The reflected ray will go towards the plane of
separation for what change of incident angle.
Analyze mathematically.
6.
a. What is refractive index?
b. Why are two eyes having in human body
advantageous?
c. Find out the relative refractive index of
medium (a).
d. What will happen to the light ray if two media
of the stem are interchange with each other
and light ray PO is incident along the same
direction? Give your opinion through
mathematical analysis.
7. An object is put 20 cm away on principal axis of a
lens of +2.5D power.
a. What is radioactivity?
b. With a normal eye, why objects of all
distance can be seen?
c. Determine the distance of that object’s image
from that lens.
d. What type of eyesight problem is remedied
with this lens? Explain with drawing ray
diagrams.
8. The near points and far points of the defective eyes of
two persons ‘A’ and ‘B’ are shown in the table below
–
Name of the
person
Near point Far point
A 15 cm 100m
B 35 cm Infinity
a. What is optical center?
b. Why is the use of optical fiber easier for the
transmitting signal at far places?
c. Calculate the power of lens of the spectacles of
the person ‘A’.
d. Explain with ray diagram how the lens of the
spectacles of the person ‘B’ forms image.
9. Observe the given figure –
a. What is lens?
b. Explain diffused reflection.
c. Determine the power of lens.
d. How can you remove the eye defect with the
help of given lens? Explain with ray diagram.
10. Grandfather of Nafis cannot see the nearer object. Eye
specialist gave him a glass of lens of power+2.25D
and suggest him to wear it.
a. What is lens?
b. “If in front of eye, flare is moved suddenly,
then in eye a circle of fire will be seen” –
Explain.
c. Determine the focal length of the glass of
grandfather.
d. Why was he (Grandfather of Nafis)
prescribed a glass of positive power? –
Explain this logically with figure.
11.
P a g e | 18
a. What center of curvature?
b. Write down the use of optical fiber in case of
medical science.
c. Determine the power of the lens.
d. The above lens is appropriate for what type of
defect of vision to eliminate? Explain with
ray diagram.
12.
a. Write Snell’s Law.
b. What is meant by the specific heat of silver is
230J kg-1K-1?
c. Determine the velocity of light in glass
medium.
d. What amount of angle of incidence will be
changed if the light has to come towards AB?
Analyze mathematically drawing the ray
diagram.
13.
a. What is critical angle?
b. What are conditions of total internal
reflection?
c. AB incident light ray changes it direction
about 11°. Calculate refractive index of water
with respect to air.
d. Pot of the above stem was filled with up sea
water and formed refracted index 1.40. Then
how much refracted ray will deviate from
incident ray? Explain with mathematical
analysis.
14. Shakil saw a reflective image on a screen kept on the
opposite side by keeping an object at a distance of
30cm from the center of curvature on the main axis
using a convex lens of 20cm focus distance.
a. What is the emergency of light called?
b. The angle of declination is mainly an incident
angle- explain.
c. What is the power of the mentioned lens?
d. Explain with the help of a ray diagram, What
steps would be needed by Shakil to see the
position of the image if the object of focus is
moved 15cm from the previous position
towards the lens.
15.
a. Write the law of Reflection of light.
b. Explain the reason for thinking about the
existence of a mirage in afternoon while
walking though a hot sandy path.
c. Determine the Refractive index of glass in the
above- given diagram in terms of water.
d. The incident angle should be how many times
greater for internal reflection to take place in
the case of emergence from glass to water?
16.
a. What is called aqueous humour?
b. Which medium is more denser between a and
b? Explain.
c. Find out the refractive index of medium a
with respect to b.
P a g e | 19
d. What will be the direction of the refracted ray
if 𝜃1 = 0°? - Explain in respect of Snell’s
Law.
17.
a. What is called regular reflection of light?
b. Refractive index of diamond with respect to
air is 2.42. what does it mean?
c. Calculate the power of the lens.
d. A person can see the distant object distinctly
but cannot see near objects distinctly. Does
the lens in the stem able to solve this
problem? Explain with ray diagram.
18. Ronjon is a student of class 10. He went to an eye
specialist for his eye problem. After examining his
eye, the doctor advised him to use a sunglass with a
focal length of 5cm and concave lens.
a. What is focal point?
b. Why do we use two plane mirrors in a simple
periscope?
c. What is the range of Ronjon’s lens according
to the doctor’s advice?
d. How will the lens help Ronjon to focus on
distant objects, according to the doctor’s
advice?
19. An object is placed on principal axis which is away
from 25cm of optical center of a convex lens of 40cm
radius of curvature.
a. What is called refractive index?
b. Explain the cause for becoming refraction of
light.
c. What is the power of the lens?
d. If the object is replaced to and fro from 10cm
position, then will the nature of image be
same? Give your opinion with ray diagram.
20.
a. What kind of mirror is used in dental
treatment?
b. What is meant by the power – 3.5d of lens?
c. In picture A, if an object is 16cm far from P.
Explain the position, size and nature of the
image by drawing a picture.
d. Which lens is suitable for remedy of the
defect created for increasing the power of
eyelens?
Chapter -10
Static Electricity
1.
Charges A and B are placed in air medium.
a. What is electric potential?
b. 220V-60W is written in an electric blub. Explain
the meaning.
c. Find out the amount of force acting between the
charges A and B.
d. If a unit positive charge is placed at the point C,
for which charge the intensity at C will be
greater? Explain mathematically.
2.
a. What is called p – n junction?
b. Explain how we can perceive the color of colored
object.
c. Find out the force between the charges A and B.
[Here constant C=9×109Nm2C-2]
d. At what position between the charges A and B if
the charge P placed so that there is no effect of
charges A and B on charge P? Give your opinion
through mathematical analysis.
P a g e | 20
3. A and B are two charged body and C is a neutral
body. The charge of A and B are -5C and +10C
respectively. The electric intensity of a point “X” is 2
NC-1 for B which is nearer to A.
a. What is electric energy?
b. Within resistance and resistivity which term is
dependent on the physical state?
c. Find the force on point ‘X’ applied by B.
d. Is it possible to convert object C into a negatively
charged object by the object A and B due to
induction? Explain with logic.
4.
a. What is called electric intensity?
b. Write down two differences between 𝛼 and 𝛾 ray.
c. What is the repulsion force between the charges?
d. What will be the change in force if the charge is
connected by an wire? Analyze mathematically.
5.
Work done to bring a +5C charge from infinity at A
and B’s electrical field is 200 J and 300 J respectively.
a. Write Coulomb’s law.
b. In the charged object’s electric field, potential
will decrease as the distance between unit objects
increases- explain.
c. Determine acting force between A and B.
d. If A and B are connected with a wire, Explain the
direction of electron flow mathematically.
6. Two charged bodies of 7.29C and 12.25C are placed
at a distance of 700 cm in air. There is a point ‘D’
between them where the electric intensity is zero.
a. What is called electric induction?
b. There is no direct connection between the electric
line and electric pillar – Explain.
c. Determine the force between the charged bodies.
d. ‘D’ is whether the middle point or not between
them – explain with mathematical logic.
7.
Two metal balls A and B of the same size and same
material is placed at a distance of 15 cm.
a. What is called electric induction?
b. What is meant by 1C charge?
c. Determine the force acting between A and B.
d. If A and B are connected by a metal wire, then
what will happen to the force? Explain
mathematically.
8.
a. What is silvering?
b. What do you mean by the value of linear
magnification is 1.5?
c. Find the value of F1 from figure -1
d. If F2 = 4F1, then what will be the value of q?
9.
a. What is called potential difference?
b. Explain whether the gap between the leaves of a
gold leaf electroscope will increase or decrease if
the substance A is touched with the disk of the
electroscope.
c. Find out the force between A & B. – Explain with
figure.
d. Is it possible to make a neutral conductor
positively charged by the substance B?
10. Two positively charged bodies having charge q1 =
30C and q2 = 4C are placed at a distance of 20m in a
vacuum. Work done in bringing the body of q1 into
the electric field of q2 and body of q2 into the electric
field of q1 is 25J and 15J respectively.
a. State Ohm’s Law.
c
P a g e | 21
b. Why extra conducting wire is used during electric
connections.
c. If the distance between q1 and q2 is made half,
then determine the force between them.
d. How will be the flow of electron when q1 and q2
are connected by conducting wire? Give your
opinion mathematically.
11.
a. What do you mean by charge?
b. An electric bulb is marked with 220V-60W. What
do you mean by it?
c. Find out the value of the effective force on B
from the above figure.
d. If the charge at B is inactive what is the value of
the electric intensity at midpoint of the straight
line between A & C?
12.
a. What is called Electric lines of force?
b. Why a metal chain is connected at the back of the
tank with petrol transporting truck?
c. Find the electric force between the two charged
body.
d. Is it possible to get a point between A and B
where electric intensity is equal? Give your
opinion by mathematical logic.
Chapter – 11
Current Electricity
1.
a. What is an electric circuit?
b. How can ‘System Loss’ be reduced?
c. Find out the equivalent resistance of the circuit.
d. If all the resistances in the stem are connected in
parallel, will the fuse be burnt for the produced
electricity? Analyze mathematically.
2. Follow the figure and answer the questions:
a. What is the relation between electric intensity and
electric lines of force?
b. What is the character of induced charge and
inducing charge? Explain.
c. Determine the difference between E and V.
(Where E and V represents usual symbol.)
d. Is it possible to get double electric current by
rearranging the resistors? Explain with
mathematical logic.
3.
a. What is called electric field?
b. If the distance between two point charge is halved
what will be the change of Coulomb force
between them? Explain.
c. Determine VB.
d. The conductivity of the material of which wire is
more? Explain with mathematical logic.
4. The current of the circuit is 1.5A.
a. What is electric circuit?
b. Explain the system loss of current.
c. Find out the energy spent in 5 minutes.
P a g e | 22
d. Will the potential difference within AD and
within DE will be same? Analyze mathematically.
5.
a. What is called electromotive force?
b. How are the area of cross-section and resistance
of conductor related? Explain.
c. Determine the equivalent resistance of the above
circuit.
d. How are the resistances of the circuit of stem
rearranged so that the flow of current will be
12.98A? Draw the circuit by analyzing
mathematically.
6.
a. What is electric capacitor?
b. If a copper wire is pulled uniformly describe the
change in its resistance.
c. Determine circuit’s equivalent resistance.
d. Between R1, R2, and R4 which one is most
powerful?
7.
a. What is the full form of MRI?
b. Explain why more current flows through the
wider wire compare to narrow wire.
c. Calculate equivalent resistance of the given
circuit.
d. What amount of money is to pay as electric bill
for one month if the given circuit runs 6 hours per
day? (Price per unit Tk 5, 1 month = 30 Days.)
8.
a. What is called electromotive force?
b. What is meant by 10 Coulomb charge?
c. Calculate the equivalent resistance of the circuit.
d. Explain with mathematical logic whether the
electric current through all the resistances in the
circuit are equal of not.
9. Follow the given circuit –
a. What is generator?
b. Explain why internet is called mother of all
network?
c. Calculate equivalent resistance for the given
circuit.
d. Will you get any change in current flow if all the
resistors are connected in parallel? Analyze
mathematically.
10.
Potential difference between B and C point is 2.2V.
a. Define electric induction.
b. If a positively charged body is kept in contact
with a negatively charged electroscope, then what
will happen? – Explain.
c. Determine the amount of flow of current through
10Ω resistance.
d. How can you arrange the given resistances to get
a equivalent resistance 7.5Ω? Explain
mathematically.
P a g e | 23
11.
a. What is called specific resistance?
b. Explain Ohm’s Law.
c. If the R1, R2, R3, resistances are connected series
and parallel separately, then determine the
equivalent resistance for both cases.
d. In parallel connection, the sum of the inverse of
the resistances is equal to the inverse of
equivalent resistance – give your opinion with
logic.
12.
a. What is called specific resistance?
b. How does electron gun work in television?
c. Calculate the equivalent resistance of the circuit.
d. The potential difference between two sides of the
resistances are same but the amount of current is
different in each resistance – Analyze
mathematically.
13.
a. What is charge?
b. Express 1kW in Joule.
c. Calculate equivalent resistance of above circuit.
d. Without changing in the value of resistance to get
2A current in the circuit, how the resistances will
be arranged? Explain the diagram.
14.
a. What is current?
b. Why is the intensity not the same at all points in
an electric field?
c. Determine the potential difference of point A and
point B of the cell.
d. Explain using mathematical explanation, what
will happen to the flow of current if all the
resistors are connected in a parallel manner by
keeping the voltage fixed.
15.
a. What is electric induction?
b. Explain why the resistance of the conductor rises
as the temperature goes up?
c. Determine the resistance from Diagram A.
d. By connecting the resistors in a parallel circuit,
prove that Rs>Rp using the Diagram.
16.
The current through the circuit is 1.5A and the voltage
of the cell is 15V.
a. What is called generator?
b. What will be the change in current if the number
of turns of secondary coil is 5 times than the
number of turns in primary coil- Explain.
c. Find out the energy spent by that cell in 5
minutes.
d. Will the potential difference between A & B and
D & E be equal?- Give your opinion with
mathematical argument.
17.
P a g e | 24
a. What is an electronic microscope?
b. If the distance between two charged particles is
doubled, what will happen to the electric force?
Explain.
c. Determine the energy of the given cell in 1
minute.
d. Explain using mathematical explanation, whether
some of the potential energy is lost in the above
mentioned circuit.
18.
a. What is called electroscope?
b. What are the safety measures should be taken in
order to maintain the electric instruments at
home? Explain.
c. Calculate the potential difference between the
point C and D.
d. How the resistances are to be connected so that
the flow of current in the circuit increase 2.5
times? Analyze with diagram.
19.
a. Write down Ohm’s Law.
b. Write down the role of a circuit breaker in a
current circuit.
c. Determine the circuit’s combined resistance.
d. Explain using mathematical explanation how will
the combined resistance of the circuit be 20Ω
through the combination of R1, R2, and R3.
20. There are three bulbs in Rahi’s house. 100W-220V,
60W-220V and 40W-220V are written on the bodies
consequently.
a. What is electric power?
b. 220V-32W is written on the body of a bulb- What
does it mean?
c. The three bulbs use 6 hours in a day. In 31 days
how much unit will be expended?
d. The filament resistance of the second bulb is more
than the filament resistance of the first one.
Analyzed with mathematical logic.
Chapter – 12
Magnetic Effect of Current
1. The ratio of the number turns of the primary and
secondary coil of a transformer is 1:50. The electric
current and voltage of the primary coil is 5A and
220V respectively.
a. What is solenoid?
b. Why motor is called the opposite instrument of
generator?
c. Find Ep: Es according to the stem.
d. From the stem mathematically show that the
electric power of the primary and secondary coil
of the transformer remains constant.
2.
a. Write elaboration of ECG.
b. Why is electric current reduced for transmission
of electricity over long distances?
c. Find the value of X from figure: A.
d. If all bulbs run at a time with the obtained value
of X in figure: B, is it possible to get the
maximum light? Give your opinion thorugh
mathematical analysis.
3.
a. What is angiography?
b. How does a speaker work? Explain it.
P a g e | 25
c. Which one is north-pole in fig 1? Explain.
d. In which direction will the wire in fig 2 acquire
resultant force? Explain it.
4. Transformer Number of turns Electric
Current
Voltage
Primary Secondary Primary A Primary Secondary
A 30 300 6A A 30 300
B 60 30 - B 60 30
a. What is called electric induction?
b. What you mean by combined circuit? Explain it.
c. Find out the electric current in secondary coil of
transformer A.
d. Which one is convenient for dwelling house and
for industrial uses by determining voltage
difference in secondary coil of transformer A and
B? Give your opinion.
5.
a. What is half-life?
b. Explain that MRI is safe and painless system to
determine disease.
c. Determine Is
d. If for Ep electrical source, instead of AC, DC is
chosen, explain how transformer will work.
6. Answer the related questions according to given
figure.
a. What is solenoid?
b. On the outer level of an engine is written ‘220V-
1000W’. What does it mean?
c. Calculate the ratio of current flow between
primary and secondary coil of the given device.
d. Analyze the importance of the given device to
supply electric current.
7. The potential difference of electricity in Rakib’s
house is 220V. But they need 660V for their fridge.
For this, he builds a transformer which contains 200
loop in its primary coil.
a. What is electromagnetic induction?
b. How can we increase induced current?
c. Find the number of loop in secondary coil at
Rakib’s transformer.
d. Mathematically show that the current of the
primary coil is 2.5 times of current of the
secondary coil.
8. The number of primary coil and secondary coil of a
transformer are 100 and 1000 respectively. The
current of primary coil is 10A. The current is changed
in secondary coil.
a. What is Solenoid?
b. Which transformer is used for current flowing-
why?
c. Determine the amount of current of secondary
coil.
d. The number of turns increased 500 in primary coil
what change of potential in secondary coil.-
Analysis.
9.
a. What is solenoid?
b. Explain what type of transformer shown in the
figure?
c. What is the current in the secondary coil?
d. Find ratio of the voltage in the primary and
secondary coil.
10.
a. What is an electromagnet?
b. Why are transformers used in transmitting
electricity?
c. Calculate secondary voltage from stem.
d. The time the device increases its ratio of voltage
is exactly equal to that it decreases its ratio of
current flow. Verify it mathematically.
11.
P a g e | 26
a. What is induced voltage?
b. Explain rule or fact on which the device has been
made.
c. Calculate the electric current in the primary coil
of this device.
d. Explain the function of this device
mathematically on the basis of data.
12.
a. What type of transformer is given in the above
stem?
b. How can you increase the strength of an
electromagnet?
c. Find the voltage of the primary circuit.
d. Is the power of the primary and secondary circuit
is conserved? Justify your statement
mathematically.
13.
a. What is Generator?
b. What do you mean by 220V-60W?
c. Determine the resistance of the secondary coil.
d. To get 110V in secondary coil, what change
should be adopted in number of turns in given
transformer? Explain mathematically.
14. The voltage in the primary and secondary coil of a
transformer are 10 volt and 20 volt respectively. The
number of turns in the primary coil is 50.
a. What is solenoid?
b. Why AC is used rather than DC?
c. Calculate the ratio of the electric current.
d. Which type of transformer is it? Analyze it
mathematically.
Chapter – 13
Modern Physics and Electronics
1. Radioactivity is a spontaneous reaction just as
radioactive rays has many benefits in our lives, it also
has many disadvantages.
a. What is an Isotope?
b. Radioactivity is a nuclear reaction- Explain.
c. Describe the significance of radioactive rays
in our daily life.
d. What effects do radioactive rays have on
animal kingdom? Explain the result.
2.
a. What is radioactivity?
b. What can you do though internet?
c. Explain the function of the signal of figure-2
d. In above stem which figure is the best to send
signal to a long distance and how does it
work?
3. Rokeya Begum was expecting a baby. She went for
medical check up to a doctor. In order to know the
size and position of the embryo the doctor suggested
her to do Ultrasonography.
a. What is echo cardiography?
b. What are the reasons for which the doctors
suggest to do angiogram?
c. Write down the role played by Ultrasonogram
for investigating the points mentioned in the
stem.
d. Are there any alternative methods for doing
the same tests of Rokeya Begum? Justify this.
4.
a. What is the elaboration of ECG?
b. Write about the uses of isotopes.
c. If the source voltage is 400V then what will
be the velocity of electron?
d. Explain the working principle of the diagram.
5.
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a. What is RAM?
b. Explain the reason of using dye during
angiography?
c. Compare the radiations mentioned in the
picture.
d. Discuss the role of 𝛼, 𝛽 and 𝛾 rays in the
welfare of human beings.
Chapter -14
Physics to Save Life
1. Raju went to doctor suffer with whole abdomen pain.
After full investigation doctor confirmed Raju’s has
gallbladder stone by X-ray.
a. Define isotope.
b. Why ‘dye’ is used in during angiography?
c. How X-ray is produced? Discuss.
d. Is it possible to examine Raju’s gallbladder
stone by using another medical instrument?
Discuss logically.
2. Examine the diagram below –
a. Draw the symbol of a diode.
b. Write down two uses of a transistor.
c. Write down the structure and working
technique of the device, which the above
given diagram represents.
d. The contribution of the given diagram in
diagnosis of diseases and medical treatment is
limitless- Explain.
3. Emon’s grandfather was a smoker. He was attacked
with cancer. Hearing the news of his grandfather’s
illness on the way to visit his grandfather he was
injured by a road accident and went to a doctor. After
checking him the doctor became sure the bone of
Emon’s leg fractured. On the other side the doctor
advised Emon’s grandfather to take radiotherapy.
a. What is ECG?
b. What can one do to save oneself from the harmful
effect of X-ray?
c. How did the doctor become sure that Emon’s
bone has been fractured? Explain it.
d. In how many ways is the treatment method of
Emon’s grandfather taken?
4. Mr. Y is a heat patient. He experiences very weakness
and respiratory problem while walking. He went to a
cardiologist and cardiologist suggested Mr. Y for
ETT.
a. How many types are radiotherapy?
b. Describe the contribution of Jagadish
Chandra Bose in Bio-Physics.
c. How ETT is done? Describe.
d. Why this test is performed instead of ECG?
Give your opinion.
