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PHYSICS LECTURE RESOURCES
Introduction to Physics and 1-D Motion
happyphysics.com
Happy Model Hr. Sec. SchoolUdhampur, India
Email: [email protected]
Prof. Mineesh Gulati
Text Book
Phundamentals of Physics F
7th Edition
Halliday, Resnick and WalkerHalliday, Resnick and Walker
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Confucius say …Confucius say …
I hear…
…….I forget
I see…
……I remember
I do…
……I understand
I hear…
…….I forget
I see…
……I remember
I do…
……I understand
lectures
slides
problems
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PtolemyPtolemy
KeplerKepler
Kelper and Tycho-BraheKelper and Tycho-Brahe
NewtonNewton
??????????
Marie CurieMarie Curie
Maria MayerMaria Mayer
YukawaYukawa
GalileoGalileo
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Earth WaterAirFire
Earth WaterAirFire
In 500 BC Physics was quite simple
KinematicsKinematics AstronomyAstronomyDynamicsDynamics
Objects stay at rest unless being pushed!
Objects stay at rest unless being pushed!
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Aristotle384 BC -322 BC
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(1971)
The retrograde motion in the orbit of mars was a serious challenge to the standard geocentric cosmology which demanded that all the planets orbit the earth. Ptolemy (85-165 AD) came up with an elaborate mechanism to keep the earth at the center of the Universe.
The retrograde motion in the orbit of mars was a serious challenge to the standard geocentric cosmology which demanded that all the planets orbit the earth. Ptolemy (85-165 AD) came up with an elaborate mechanism to keep the earth at the center of the Universe.
September 4
July 26
June 6October 14
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Ptolemy’s Epicycles (85-165 AD)
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Crystal sphere with starsCrystal sphere with stars
ParadiseParadise
EarthEarth
Can you imagine no change to this theory for more than 1000 years!
Can you imagine no change to this theory for more than 1000 years!
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Copernicus ~1540
Earth revolves around the Sun ---365 days
Earth rotates on its axis -- 1 day
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Retrograde motion according to Copernicus
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Galilei Galileo 1564 - 1642happyphysics.com
Kepler’s Laws of Planetary Motion
Johannes Kepler 1571-1630
Law 1 The planets circulate in eliptical orbits with the sun at one focus
Law 1 The planets circulate in eliptical orbits with the sun at one focus
Law 2 A line joining the planet to the Sun sweeps out equal areas per unit time.
Law 2 A line joining the planet to the Sun sweeps out equal areas per unit time.
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The law of areas
When closer to the sun, the planet moves faster
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A CHRONOLOGY OF THE SCIENTIFIC REVOLUTION
1440 Gutenberg completed his wooden press which used metal moving type.
1543 Nicolas Copernicus publishes On The Revolutions of the Heavenly Spheres
1571 Tycho Brahe develops instruments for precise astronomical observation and records positions of stars and planets. He creates a Tychonic System of the cosmos called geoheliocentric. Planets revolve around the sun, while the sun and planets still revolve around the central earth
1609 Johannes Kepler publishes his first and second Laws of Planetary motion. (l) Planetary orbits are elliptical.
(2) Planets sweep out equal areas in equal times
1609 Galileo Galilei develops a telescope of 30X magnification and begins observations
1619 Kepler announces his Third Law of Planetary Motion which stated that a planet's distance from the sun is related to the time it takes a planet to revolve around the sun
1632 Galileo publishes his Dialogues on the Two Chief Systems of the World which popularized the Copernican system and articulated the concept of a world subject to mathematical laws
1633 Galileo is denounced by the Inquisition and forced to recant his belief in Copernican theory
1667 Sir Isaac Newton constructs the first reflecting telescope
1687 Newton publishes his Principia Mathematica which explained gravitation, contained the components of Newtonian Physics (matter, motion, space, attraction), and challenged the Aristotelian/Ptolemaic cosmos.
A CHRONOLOGY OF THE SCIENTIFIC REVOLUTION
1440 Gutenberg completed his wooden press which used metal moving type.
1543 Nicolas Copernicus publishes On The Revolutions of the Heavenly Spheres
1571 Tycho Brahe develops instruments for precise astronomical observation and records positions of stars and planets. He creates a Tychonic System of the cosmos called geoheliocentric. Planets revolve around the sun, while the sun and planets still revolve around the central earth
1609 Johannes Kepler publishes his first and second Laws of Planetary motion. (l) Planetary orbits are elliptical.
(2) Planets sweep out equal areas in equal times
1609 Galileo Galilei develops a telescope of 30X magnification and begins observations
1619 Kepler announces his Third Law of Planetary Motion which stated that a planet's distance from the sun is related to the time it takes a planet to revolve around the sun
1632 Galileo publishes his Dialogues on the Two Chief Systems of the World which popularized the Copernican system and articulated the concept of a world subject to mathematical laws
1633 Galileo is denounced by the Inquisition and forced to recant his belief in Copernican theory
1667 Sir Isaac Newton constructs the first reflecting telescope
1687 Newton publishes his Principia Mathematica which explained gravitation, contained the components of Newtonian Physics (matter, motion, space, attraction), and challenged the Aristotelian/Ptolemaic cosmos.
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JOHANNES VERMEER
~1660
The year Newton postulated gravity!
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The Astronomer
Vermeer 1668
The Geographer
Vermeer 1668/9
These paintings reflect the blossoming of scientific enquiry in seventeenth century Europe.
At this time, Newton is making the first reflecting telescopes,
Louis XIV is building an observatory in Paris,
the satellites of Jupiter are being used for navigation at sea, and
Huygens has discovered the sixth satellite of Saturn.
The old views, that it would be presumptive for man to probe too closely the sky or the Earth, are being replaced by modern principles of science.
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Woman peeling potatoes Gabriel Metsu (~1660)
Courtyard (1658)
Pieter de Hooch
Milkmaid Vermeer (~1660)
Sick ChildSick Child Gabriel Metsu (1660)
At this time artists began to paint pictures of everyday people and events.
Women and their children
The everyday tasks of caring for a family
The caring love for a sick child
At this time artists began to paint pictures of everyday people and events.
Women and their children
The everyday tasks of caring for a family
The caring love for a sick child
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Monteverdi
Bach
Vivaldi
Scarlatti
Purcell
Mozart
Handel
And over this same period, as Physics became liberated and questioning, as architecture flourished, and art became less constrained and reflected the real world, there developed a blossoming of music.
The baroque period: new enlightened and liberated forms of music, and newly developed instruments.
The chamber works of Vivaldi
The splendor of Bach’s organ works
The choral works of Monteverdi and Handel
The new opera works of Purcell
The genius of Mozart
So we see that in this revolutionary time, Physics was ready for Newton (born in1643), to revolutionize our understanding of mechanics..
And over this same period, as Physics became liberated and questioning, as architecture flourished, and art became less constrained and reflected the real world, there developed a blossoming of music.
The baroque period: new enlightened and liberated forms of music, and newly developed instruments.
The chamber works of Vivaldi
The splendor of Bach’s organ works
The choral works of Monteverdi and Handel
The new opera works of Purcell
The genius of Mozart
So we see that in this revolutionary time, Physics was ready for Newton (born in1643), to revolutionize our understanding of mechanics..
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Isaac Newton
1642-1727happyphysics.com
Why is it so!!!
Riding a bikeRiding a bike
The unstable topThe unstable top
Racing down hillRacing down hill
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For you to read by next lecture
Review of Year 12 Physics2.3 Defining position in 1D2.4-2.6 Definitions of average and instantaneous
speed and acceleration in 1D. The relationships between these
2.7 The case of constant acceleration (VCE Physics)
Read this for next lecture3.2- 3.6 Specifying vectors
Sections from the Text book:
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For Next Lecture:What is her average speed?What is her average velocity? What do you mean by velocity?
To think about:
1 k
m 2 km
If she rode directly to school, what would be her speed? Velocity?
I will quiz you on this next lecture.I will quiz you on this next lecture.
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Here endeth
the lessonlecture
No. 1
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Rectilinear Motion
StraightStraight lineline MotionMotionKinematicsKinematics
HOW things moveHOW things moveDynamicsDynamics
Erect = straight
WHY things moveWHY things movehappyphysics.com
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xDistance travelled in equal time intervals
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x
Time (t)
Dist (x)
x
x
x
x
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Time (t)
Dist (x)
x
x1
t1
x2
x3
x4
x5
t2 t3 t4 t5
t
x
tt
xxavv
34
34
Dx
Dt
Average speedspeed = distance .
time taken
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Gradient of the x-t curve
Time (t)
Dist (x)
x
x1
x2
x3
x5
x6
t3
x4
t4
Dx
Dt
x4
t4
Dx
Dt
tx)t(v
0t
limit
dt)t(dx
)t(v
Instantaneous speed
t
x
tt
xxavv
34
34
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dt)t(dx
)t(v
If we know x(t), we can find v(t)
Position (x)
Position as a function of time
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dt)t(dx
)t(v
If we know x (t), we can find v(t)
time
time
time
Speed as a function of time
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dt)t(dx
)t(v
If we know x (t), we can find v(t)
dt)t(dv
)t(a
Similarly if we know v(t), we can find a(t) since
time
time
time
Acceleration as a function of time
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If we know a(t), we can find v(t), since:
dttatvfinalt
initt
.)()(
And from v(t) we can find x(t), since
finalt
inittdttvtx )()(
From acceleration speed distance
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If acceleration is constant, life is easy!
VCE easy
t0 t (t)
(acc
el)
(t)
spee
d
v0
atvv 0
Similarly
x-x0= v0t + ½ at2
v2 = v02 + 2as etc.
o
o
tt
vva
t
vva o
if t0 = 0,
See slide lect 2
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1-D (linear kinematics)
with constant acceleration
1-D (linear kinematics)
with constant accelerationVCE Physics
See modified slide lecture 2
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2-D Kinematics
have magnitude and direction
distance displacement
speed velocityhappyphysics.com
Distance from Melbourne to Bendigo = 1600 km
Displacement of Bendigo rel. to Melbourne = 200 km (NW)
Average velocity = displacement/time = 200/2 = 100 km/h N.W.
Average speed= distance/time = 1600/20 = 80 km/h
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Y
X
P1 (x1, y1)
P2 (x2, y2)
y1
y2
x1 x2
r1
r2
12
r1 = ix1 + jy1 +( kz1)r2 = ix2 + jy2 +( kz1)
r
r = i(x2- x1) + j(y2-y1) +r = i x + j y +
y
x
r = r2 - r1
r = (ix2 + jy2) -(ix1 + jy1)
r1 is the vector displacement of P1rel to originr2 is the displacement vector of P2 rel to origin r is the displacement vector of P2 rel to P1
The length of r1= 21
21 yx
Unit vectors
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P1 (x1, y1)
P2 (x2, y2)
12
r
Y
X
y1
y2
x1 x2
r1
r2
y
x
t
rvav
dt
rd)t(v
t
r
0)t(v
t
limit
Average velocity
Vav is in direction of Dr
Instantaneous
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