Free Test01

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physics

Q. 1

A 2m wide truck is moving with a uniform speed v0 = 8 m/s along a straight horizontal road. A pedestrian starts to cross the road with a uniform speed v when the truck is 4 m away from him. The minimum value of v so that he can cross the road safely is

0

1.2.62 m/s

2.4.6 m/s

3.3.57 m/s

4.1.414 m/s

1 marks

Q. 2

From an inclined plane two particles are projected with same speed at same angle , one up and other down the plane as shown in figure. Which of the following statement is correct?

0

1.the particles will collide the plane with same speed

2.the times of flight of each particle are same

3. both particles strike the plane perpendicularly

4.

the particles will collide in mid air if projected simultaneously and time of flight of each particle is more than the time of collision.

1 marks

Q. 3

Velocity-time graphs of a particle moving in a straight line is shown in the figure. Mass of the particle is 2 kg. Work done by all the forces acting on the particle in time interval t = 0 to t = 10 sec is

0

1.300 J

2.- 300 J

3.zero

4.- 400 J

1 marks

Q. 4

A particle is moving in x-y plane with y = x/2 and vx = 4 - 2t. The displacement versus time graph of the particle would be

0

1.

2.

3.

4.

1 marks

Q. 5 Two particles having position vectors and are

moving with velocities 2 sec, the value of ?a' is

and

If they collides after

0

1.2

2.4

3.6

4.8

1 marks

Q. 6

A particle P is sliding down a frictionless hemispherical bowl. It passes the

point A at t = 0. At this instant of time, the horizontal component of its velocity is v. A bead Q of the same mass as P is ejected from A at t = 0 along the horizontal string AB, with the speed v. Friction between the bead and the string may be neglected. Let tP and tQ be the respective times taken by P and Q to reach the point B. Then

0

1.tP < tQ

2.tP = tQ

3.tP > tQ

4.

1 marks

Q. 7 A particle of mass m = 5 units is moving with a uniform speed unit in x-y plane along the line y = x + 4 in given reference frame. If at t = 0 particle was at (0,4). Moment of inertia of mass about the x-axis at t = 1 sec will be

0

1.340 units

2.80 units

3.60 units

4.245 units

1 marks

Q. 8

In the gravitational field two masses are projected with the same horizontal velocity from different points as shown in the figure. The time taken by the 2m mass to reach the ground after the m mass strikes the ground, is

0

1.sec

2.sec

3.1 sec

4.2 sec

1 marks

Q. 9

Block B moves downward with a constant velocity of 0.6 m/s. Then

0

1.the velocity of block A is 0.9 m/sec

2. the velocity of block C is 0.1 m/sec

3.the velocity of portion D of the cable is 5.0 m/sec

4.the relative velocity of portion D of the cable with respect to block B is 3.0m/sec

1 marks

Q. 10 A person traveling eastwards finds that the wind appears to blow directly from north. On doubling his speed it seems to come from north-east. If he trebles his speed in what direction it would appear to blow?

0

1.in the direction making an angle sin-1 to east of south

2.in the direction making an angle sin-1 to north of east

3.in the direction making an angle tan-1 to north of east

4.in the direction making an angle cos-1 to west of north

1 marks

Q. 11 A particle of mass m is executing oscillations about the origin on the x axis. Its potential energy is V (x) = k | x |3where k is a positive constant. If the amplitude of oscillation is a, then its time period T is

0

1.Proportional to 1/

2. Independent of a

3.Proportional to

4.Proportional to a3/2

1 marks

Q. 12 A particle is moved from (0, 0) to (a, a) under a force from two paths. Path 1 is OP and path 2 is OQP. Let W1 and W2 be the work done by this force in these two paths. Then

0

1.W1 = W 2

2.W1 = 2W2

3.W2 = 2W1

4.W2 = 4W1

1 marks

Q. 13 A self-propelled vehicle of mass m, whose engine delivers constant power P, has an acceleration a = P/mv (assume that there is no friction). In order to increase its velocity from v1 to v2, the distance it has to travel will be.

0

1.

2.

3.

4.

1 marks

Q. 14 Force acting on a particle is . Work done by this force is zero, when a particle is moved on the line 3y + kx = 5. Here value of k is

0

1.2

2.4

3.6

4.8

1 marks

Q. 15 A particle moves in the x-y plane under the action of the force the value of its linear momentum The angle between and such that

at time t is: px = 2 cos t and py = 2 sin t.

at time t will be:

0

1.900

2.00

3.1800

4.300

1 marks

Q. 16 A particle is displaced form x = -6 m to x = +6m. A force F acting on the particle during its motion is shown in figure. Graph between work done by this force (W) and displacement (x) should be

0

1.

2.

3.

4.

1 marks

Q. 17 A ball of mass 50 gm and relative density 0.5 strikes the surface of water with a velocity of 20 m/s. It comes to rest at a depth of 2 m. Find the work done by resisting force of water.

0

1.-6 J

2.+7.5 J

3.-9.0 J

4.-10 J

1 marks

Q. 1 8

0

1.

2.

3.

4.

1 marks

Q. 19 An object of mass m slides down a hill of height h of arbitrary shape and after travelling a certain horizontal path stops because of friction. The friction coefficient is different for different segments for the entire path but is independent of the velocity and direction of motion. The work that a force must perform to return the object to its initial position along the same path is

0

1.mgh

2.2mgh

3.4mgh

4.-mgh

1 marks

Q. 20 A bob is suspended from a crane by a cable of length l = 5m. The crane and load are moving at a constant speed v0. The crane is stopped by a bumper and the bob on the cable swings out an angle of 600. The initial speed v0 is (g = 9.8 m/s2)

0

1.10 m/s

2. 7 m/s

3.4 m/s

4.2 m/s

1 marks

Q. 21 A metallic wire of density d floats horizontal in water. The maximum radius of the wire so that it may not sink, will be (surface tension of water = T)

0

1.

2.

3.

4.

1 marks

Q. 22 A big drop of radius R is broken into 27 equal small drops under isothermal condition. Work done in the process is - (S Surface tension)

0

1.

2.

3.

4.No work is done.

1 marks

Q. 23 The height of water in a vessel is h. The vessel wall of width b is at an angle to the vertical. The net force exerted by the water on the wall is

0

1.

2.

3.

4.zero

1 marks

Q. 24 An electric dipole is placed at center of sphere. Which of the following option are correct. (i) flux of electric field through sphere is zero. (ii) electric field is zero at every point of sphere. (iii) electric field is non-zero any where on sphere (iv) electric field is zero on a circle on sphere

0

1. only (i)

2.only (ii)

3.only (i) and (iii)

4.all are correct

1 marks

Q. 25

In the figure the potentiometer wire of length l = 100 cm and resistance 9 is joined to a cell of emf E1 = 10V and internal resistance r1 = 1 another

cell of emf E2 = 5V and internal resistance r2 = 2 is connected as shown. The galvanometer G will show no deflection when the length AC is:

0

1.50 cm

2.55.55 cm

3.52.67 cm

4.54.33 cm

1 marks

Q. 26 The metal plate on the left in figure carries a charge +q. The metal plate on the right has a charge of -2q. What charge will flow through S when it is closed, if central plate is initially neutral

0

1.zero

2.-q

3.+q

4.+2q

1 marks

Q. 27 A dielectric slab of area A and thickness d is inserted between the plates of capacitor of area 2A and distance between plates d with a constant speed v as shown in figure. The capacitor is connected to a battery of emf E. The current in the circuit varies with time as

0

1.

2.

3.

4.

1 marks

Q. 28 One plate of a capacitor is connected to a spring as shown in figure. Area of both the plates is A. In steady state separation between the plates is 0.8d (spring was unstretched and the distance between the plates was d when the capacitor was uncharged). The force constant of the spring is approximately

0

1.

2.

3.

4.

1 marks

Q. 29 The potential field depends on x and y coordinates as V = (x2 - y2) corresponding electric field lines in x-y plane are as

0

1.

2.

3.

4.

1 marks

Q. 30 An electric dipole is placed inside a non-uniform electric field, increasing at the rate of per unit distance, along Z-axis. The dipole can undergo:

0

1.rotational motion only.

2.transnational motion along Z-axis only.

3.a rotational motion as well as a translation motion along Z-axis.

4.None of these.

1 marks

Q. 31 Two mol