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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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CHAPTER 3
MOTION
Contents:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
REST, MOTION AND TYPES OF MOTION.
DISTANCE AND DISPLACEMENT
SPEED, VELOCITY, ACCELERATION AND TYPES WITH EQUATIONS OF MOTION
ACCELERATION DUE TO GRAVITY AND EQUATION
LAWS OF MOTION.
TENSION AND TWO SPECIAL CASES
MOTION INCLINED PLANE
LINEAR MOMENTUM AND MOMENTUM IN TERMS OF SECOND LAW OF MOTION
LAW OF CONSERVATION OF MOMENTUM
ELASTIC, INELASTIC COLLISION. & ELASTIC COLLISION ON ONE DIMENSION
EQUATIONS
DIMENSIONS
13. SHORT QUEASTIONS AND ANSWERS
Classical Mechanics:
Classical Mechanics is a part of Physics and describes the behavior of
bodies with forces acting upon them. Classical Mechanics is often referred
to as "Newtonian Mechanics" as Newton formulated the fundamental laws
of motion on which Classical Mechanics is based. Classical Mechanics is
divided into:
statics - studies of objects at rest,
kinematics - studies of objects in motion, without considering the forces
acting upon them,
dynamics - studies of motion under influence of force.
TECHNECHAL TERM RELATIVE DEFINITIONS
1. Frame of reference:
2. Rest: 

While we observe a body that does not change its
position with flow of time, we almost unknowingly refer
to a second body which is nearby the first one. The second body should be a fixed one - it may be a
domestic building or a tree, a lamppost or a prominent spot oh a road or a fixed star in the sky. This second
body is called a reference body or a frame of reference.

A body is said to be at rest if it does not change its position with time from a
fixed neighboring object.
3. Motion: 
 A body is in motion, if its position from a fixed neighboring object changes with time.
In physics we are concerned with three types of motion: i) Translational or Linear, ii) Rotational or Angular, and iii)
Vibrational or Oscillatory. A car moving down a highway is an example of translational motion, the Earth’s spin on its axis is an
example of rotational motion, and the back-and-forth movement of a pendulum is an example of vibrational motion.
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
1-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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4. Rest and motion are relative:
A body seems to be at rest with respect to one neighboring fixed object but the same body may
appear to be in motion with respect to some other fixed neighboring object So, rest and motion are relative
terms.
5. Distance: 
 The distance of a body is defined as its change in position.
Distance is a scalar quantity; it is the path between two distinct poison points similar to one type of length in nature has unit
meter and dimension [L].
6. Displacement: 

When an object changes its position as time passes on, the distance measured in the direction
from its initial to final position along a straight line is known as its displacement.
Displacement is a vector quantity; it is directed from the initial position of a body to its final position. Unit in C.G.S
system is cm and in M.K.S. system is m and dimension [L]. Thus, distance is the magnitude of displacement.
7. Speed: 

Speed of an object, is the Total distance (d) traveled per Time (t) in straight line.
d
Speed =
t
It is derived scalar quantity. The unit of speed in MKS system is m.sec-1 and dimension is [ LT-1 ].
8. Linear Velocity: 
 The Velocity of an object is the rate of change of Displacement in time.
The displacement ( S ) covered by a body in unit time (t) along straight line, is called its “velocity” or “linear velocity”. It is
derived vector quantity.
v=
S
t
S
The magnitude of velocity is,   same as speed .The direction of velocity is same as the direction of displacement. The unit of
t
velocity in MKS system is m.sec-1 and dimension is [ LT-1 ]. Thus speed is the magnitude of velocity.
a) Uniform velocity: 

If the speed and direction of moving body does not change with time then its
velocity is said to be uniform velocity.
v=
b) Variable velocity: 

FIRST YEAR
S
t
If the speed or direction changes with time then the velocity of such a body
is said to be variable velocity.
CHAPTER 3
2010 – 2011
MOTION
2-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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v=
c) Relative velocity: 

S
t
When two bodies are in motion the velocity of one body, relative to the other is called
relative velocity.
v=
d) Instantaneous velocity: 
S
t

Instantaneous velocity is the velocity at a given instant.
 ΔS 
 as t approaches zero: Instantaneous velocity is
Instantaneous velocity vinst equals the limiting value of the ratio 
 Δt 


the derivative of displacement with respect to time.
 Δs 


Δv= Δtlim
0  Δt 


8. Linear Acceleration: 

The continuously change of velocity of a body in unit time along straight line,
is called its “Linear acceleration” or acceleration or it is the rate of change of velocity in
time.
v -v
change of velocity
Acceleration =
 f i
Thus,
time
t
v v
a= 
t
t
v
The magnitude of acceleration is   and its direction is same as the direction of velocity .The acceleration is derived
t
vector quantity, of unit m. sec-² in MKS system and dimension  LT -2  .
The continuous rate of increase of velocity in time is called “positive acceleration” (+ a). And continuous rate of decrease of
velocity in time is called “negative acceleration” or retardation or deceleration (- a).
a) Instantaneous Acceleration: 

The continuous change of velocity of a body with time, as time approaches to zero
is called “Instantaneous acceleration”.
 v 
 a = lim  
t  0 t
 
Instantaneous acceleration is the derivative of velocity with respect to time
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
3-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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10. Equation of Motion: 
For uniform motion,
For accelerated motion,
s=vt
v f = vi + a t
s = vi t +
1 2
at
2
2as = vf2 - vi2
11. Acceleration due to gravity: 

Objects thrown upward or downward and those released from rest are all falling
freely once they are released. Any freely falling object experiences change of velocity
uniformly in unit time directed downward, regardless of its initial motion. Such acceleration
is called “acceleration due o gravity”.
We shall denote the magnitude of the free-fall acceleration by the symbol “g”. The value of “g” depends on altitude, at the
Earth’s surface the value of g is approximately 9.80 m/s2.
Equations for acceleration due to gravity: 
v f = vi + g t
h = vi t +
1 2
gt
2
2gh = vf2 - vi2
12. Mass and weight: 
13 Forces:

Mass is that property of an object that specifies how
much inertia the object has, the SI unit of mass is the kilogram. The
greater the mass of an object, the less that object accelerates under
the action of an applied force. Mass is an inherent property of an object
and is independent of the object’s surroundings and of the method
used to measure it. Also, mass is a scalar quantity.

Weight is therefore an extrinsic property depending on
the strength of gravitational acceleration to which a body is subjected
and so would be smaller at the top of a mountain than at the
mountain's bottom, while mass is an intrinsic property. Weight
describes the pull of gravity on mass. In fact, it is the mass of the object times the acceleration due to the
gravity acting on it. Weight, thus, is the gravitational force exerted on an object.
W=mg

The concept of the force is important to the development of mechanics and all of physics. A
force is a "push" or "pull" experienced by a mass m when it is accelerated
. The SI unit of force is the Newton, equal to 1 kg m s-2. The cgs unit of force is the dyne, and the British engineering unit of force
is the pound.
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
4-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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14. Laws of Motion: 
The science of mechanics is based on three laws of motion, explained by Sir Isaac Newton, are also called
Newton’s laws of motion.
First law of Motion:

An object at rest will remain at rest unless acted on by an unbalanced force. An object in
motion continues in motion with the same speed and in the same direction unless acted upon by an
unbalanced force.
Explanation:
A glass of water placed on a table remains there unless a force is applied to remove it. Similarly, if a car is moving with
uniform velocity, it goes on moving with the uniform velocity. Objects will remain in their state of rest or motion unless a force acts
to change the motion. Any change in motion produces acceleration. This law is often called "the law of inertia". This means that
there is a natural tendency of objects to keep on doing what they're doing. All objects resist changes in their state of motion. In the
absence of an unbalanced force, an object in motion will maintain this state of motion.
Inertia of Rest and Inertia of Motion:
Inertia of a body is its reluctance to change the state of rest or of uniform motion. It is also the degree of resistance a material
body can offer to change of motion or rest condition. Inertia is of two types :(i) inertia of rest, (ii) inertia of motion.
Inertia of rest: Inertia of rest is the inherent property of a material body by virtue of which it continues in its state of rest until and
unless no external unbalanced force compels it to move.
Inertia of motion: The tendency of a moving body to maintain its uniform motion in a straight line in absence of an effective
external force is called inertia of motion
Second law of Motion:

The resultant force acting on a body will cause the body to accelerate in the
direction of the resultant force. The acceleration of the body is directly proportional to the
magnitude of the resultant force and inversely proportional to the mass of the object.
1
Fnet  a
And a 
m
Therefore
Fnet = m a
Explanation:
When an external unbalanced force acts on a body then it generates acceleration in the direction of applied force. As force
increases, acceleration also increases in the same direction along straight line, under constant mass.
Mathematically:
F =ma
The magnitude of force is given by, F = ma
Force:
Force is, “The product between mass and acceleration” .It is a vector-derived quantity.
Force is calculated in “Newton” and “Dyne” in metric system of units. Its dimension is [MLT−²].
Newton:
One kilogram mass produces an acceleration of 1m / sec2 in the direction of force then the force is called “One Newton”.
F=ma
F = (1 Kg) 1 m / sec²
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
5-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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1N = 1 Kg. m / sec²
Dyne:
 One gram mass produces an acceleration of 1cm / sec² in the direction of force then the
force is called “One Dyne”.
F=ma
F = (1 gm) 1 cm / sec²
1 dyne = 1 gm. cm / sec²
Relation between Newton and Dyne:
F = ma
1N = (1Kg) 1m/sec²
1N = (1000 gm) 100 cm / sec²
1N = 105 (gm cm / sec²)
1N = 105 dynes
Third law of Motion:
Every action there is an equal and opposite reaction, differently bodies operate against each other with
the forces directed along one straight line, equal on the module and opposite in a direction.
Explanation:
Suppose a block exerts a force equal to its weight “W” on to a table, then it exerts an equal and opposite force called normal
reaction “R” on to a block. Thus, Forces always occur in pairs.
Faction = - Freaction
DESCRIPTIVE
PART
15. Tension in the string:

"The force exerted by a string when a string is pulled", such force exerted by the string, on to the suspended
body is called “Tension” in the string, denoted by “T”.
Explanation:
Consider a block of mass “m” which is suspended from a fixed beam by means of a string.
The string is assumed to be light and inextensible. The string is stretched, since it is being pulled
at both ends by the block and the beam. The string must be being pulled by oppositely directed
forces of the same magnitude. By Newton's third law, the string exerts oppositely directed forces
of equal magnitude T, on both the block and the beam. These forces act so as to oppose the
stretching of the string, the beam experiences a downward force of magnitude “T”, whereas the
block experiences an upward force of magnitude “T”. Where, T is termed the Tension of the
string. Since T is a force, it is measured in Newton’s.
 Calculation of Tension in the string and Acceleration in two unequal masses, when move
vertically:
Consider two masses, “m1” and “m2” connected by a light inextensible string which is suspended from a frictionless pulley.
Let us assume that mass “m1” is going to move downwards. The first mass is subject to an upward force ”T”, due to the tension in
the string, and a downward force“m1g” , due to gravity. The net force cause the mass to move downwards with acceleration is,
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
6-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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For the mass “m1”:
According to the second law of motion, F = m a, the unbalanced force acted on it is ( m1g – T ).
Therefore,
[m1 g –T] = m1 a
--------------►eq. (1)
The second mass “m2” is subject to a upward force, due to gravity “m2 g”, and an upward force “T”, due to
the tension in the string. The net force cause the mass to move upward with acceleration is,
For the mass “m2”:
According to the second law of motion, F = m a, the unbalanced force acted on it is (T– m2 g).
[T – m2 g] = m2 a
--------------►eq. (2)
Calculation of “a”:
By adding equations 1 and 2, we get,
[ m1 g – T ] + [ T – m2 g ] = (m1 a) +( m2 a)
m1 g – m2 g = m1a + m2 a
g ( m1 - m2 ) = a ( m1 + m2 )
g  m1 - m 2 
a=
 m1 + m 2 
Calculation of “T”:
Divide equation 1 by equation 2 ,
 m1g -T  = m1a
 T- m 2g  m 2a
 m1g -T 
 T- m 2g 
m1
m2
m2 ( m1 g -T ) = m1 ( T- m2 g )
m2 m1 g - m2 T = m1 T - m1 m2 g
m1 m2 g + m1 m2 g = m1 T + m2 T
2 m1 m2 g =T ( m1 + m2)
2 m1m2g
T=
 m1 + m2 
=
g 
Show that, a =   , when m1= 3m2 , while vertical motion.
2
Proof:
g  m1 - m 2 
We know that, a =
 m1 + m 2 
a=
a=
FIRST YEAR
g  3m 2 - m 2 
 3m 2 + m 2 
g  2m 2 
 4m 2 
CHAPTER 3
2010 – 2011
MOTION
7-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
ADDRESS: Behind ALFALAH BANK, Grain Market, Branch. Prince Ali Road, Near Sadaf Plaza.
CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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g
, This shows that, vertical acceleration in two masses becomes one - half the
a=
 2
acceleration due to gravity, when larger mass becomes three times the smaller mass.
Show that W =T, When two bodies of equal masses suspended vertically.
Proof:
2 m1 m 2 g
Suppose, m1 = m2, and we know that, T =
(m1 + m 2 )
2 m1 m1 g
T=
(m1 + m1 )
2 m12 g
(2m1 )
T = m1 g
T= mg
T = W This shows that, Tension in the string is equal to the weight of vertical suspended masses
T=
 Calculation of Tension in the string and acceleration in two masses, while one mass moves
vertically while the other horizontal:
Consider two masses, “m1” and “m2”, connected by a light inextensible string. Suppose that mass “m2” slides over
a smooth, frictionless, horizontal table, while the, mass“m1”” is suspended over the edge of the table by means of a light
frictionless pulley. No force is required to turn a frictionless pulley, so we can assume that the tension “T” of the string is the same
on either side of the pulley. Let us apply Newton's second law of motion to each mass. The net forces cause the mass to move
downwards with acceleration
Let us derive expressions for calculating the “a” in the masses and “T” in the uniform string.
For the mass “m1:
According to the second law of motion, F = ma,
The net unbalanced force acting on it is (m1 g –T).
m1 g –T = m1 a
--------------►eq.(1)
For the mass “m2”:
According to the second law of motion, F = m a,
The unbalanced force is only “T”. Because, R (normal reaction force) = m2 g (weight of a body), balanced each other.
T = m2 a
--------------►eq. (2)
Calculation of “a”:
By adding equation 1 and 2, we get,
( m1 g –T ) + T = m1 a + m2 a
m1 g = m1 a +m2 a
m1 g = a ( m1 + m2 )
m1 g
a=
 m1 +m2 
Calculation of “T”:
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
8-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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COMPOSSED AND WRITTEN BY PROF. NAJEEB MUGHAL. GOVT. MUSLIM SCIENCE DEGREE COLLEGE HYD.
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By putting the value of “a” in equation 2, we get,
 m1 g

T = m2 

  m1 + m 2  
 mm g 
T=  1 2

  m1 + m 2  
Show that T1 = 2T2
Proof:
2 m1m2g
We know, T1 =
, when two unequal masses move vertically.
 m1 + m2 
 mm g 
T2 =  1 2
 , when one mass moves vertically while the other horizontal.
m
+
m


1
2


By dividing both equations,
 2 m1m 2 g 

 m1 + m 2  
T1

Thus ,
=
T2
 m1m 2 g 


  m1 + m 2  
And
T1  2 m1m 2 g    m1 + m 2  



T2   m1 + m 2    m1m 2g 
T1
2
T2
We get ,
T1 =2T2
Thus, “Tension in the string, when two unequal masses suspended at the ends of string move vertically is equal to the twice the
tension; when one mass moves vertically while the other mass horizontal.”
16. Friction:

When an object is pushed we feel some kind of resistance. A frictional force is
created when the object has been given a tendency of motion. Therefore it acts in the opposite
direction in order to resist the motion.
Co-efficient of friction:

The ratio of limiting friction (F) to the normal reaction force (W = m g = R) acting between two
surfaces in contact is called the “Co-efficient of friction”, denoted by.
F
μ=
R
F=R
Limiting friction:
FIRST YEAR
CHAPTER 3
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MOTION
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
The force of friction is due to the roughness of material surfaces in
contact. If the surfaces are smooth then there is no force of friction. The friction is
self-adjusting force it does not increase indefinitely with the external force. If the body
at the point of sliding then the force exerted called is “Limiting force of friction”. It is
maximum value of static friction.
Static Friction

Kinetic Friction
Static friction is the friction between two surfaces before they start moving against each other.
This is the resistance that you feel when trying to slide a box across the floor. Before, the box starts moving;
there is a resistance due to the static friction between the floor and box. Once the box starts moving, Fs = s R

Kinetic friction takes over. Kinetic friction is the resistance between two rubbing surfaces.
Through experience, most people know that it is harder to get the box moving compared to maintaining its
motion. This is because static friction is always larger than kinetic friction. Fk = k R
Frictional forces depend on the types of surfaces on surfaces. These coefficients can equal one or zero and anything in
between, but they cannot be greater than one or less than zero.
Fluid Friction:
 The resistance to an object's motion through a fluid may be termed "Fluid Friction."
It may take the form of viscous resistance in a liquid, or the rather different character of air friction when an object moves through
a gas.
According to Stokes Law the, f = 6   r v
Where ‘ ’ is the coefficient of viscosity and, “r” is the radius of the sphere moving with velocity “v”.
17.  Motion on an inclined plane:
 A sloping plane, which makes an angle with the
horizontal, is called, “Inclined plane.”
Explanation:
Consider a body of mass “m” is placed on an inclined surface
making an angle “” with the horizontal. The weight (W) of a body is
acting vertically downward, makes same angle with the normal reaction (
R ) . The weight is to be resolved in to its rectangular components, we
get, W Cos perpendicular and W Sin parallel components to the
inclined surface.
If the force of friction “f” opposes the motion of body then a body
will remain in the state of rest, According to the first condition of
equilibrium.
 Fx = 0
f + ( - W Sin θ ) = 0
f = W Sinθ
And
 FY = 0
R + ( - W Cosθ) = 0
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
10-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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R = W Cosθ
Suppose a body is sliding to wards the bottom point of slope, with acceleration “a”. A body is in the
state of motion due to the, second law of motion. F = m a. The net unbalanced force acts on it is (m g Sin  f).
Thus,
( m g sin - f ) = m a
( m g sinθ - f )
ma
=
m
m
mg sinθ f
 a
m
m
f 
g sinθ     a
We get,
m
If the force of friction is zero, (say f = 0),
0
g sinθ     a
Then,
m
g sinθ = a
This shows that, “if force of friction is not present, then motion of a
body is independent of mass
of a body”.
Special cases:
i) When,  = 0o
Then, a = g sin 0o
a = 0, (because, Sin 0o = 0). A body remains in the state of rest, on horizontal plane.
ii) When,  = 60o
Then, a = g sin 60o
a = g (0.5),
1
g
2
Thus, a = 4.9 m / sec2
iii) When,  = 90o
Then, a =g Sin 90o
a = g = 9.8 m / sec2 , ( because, Sin 90o = 1 ). A body falls freely, under the influence of gravity.
Above cases show that as the slope angle “” increases the motion “a” of body increases
a=
18. Linear momentum:
Linear momentum is a measure of an object's translational motion.
on to Mass and Velocity of a body. It means,
 “The product between mass and velocity of a body is called Momentum”.
Where,
linear momentum = m v
p=mv
FIRST YEAR
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MOTION
The momentum depends
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The linear momentum of a body of mass “m” moving with a velocity “v” is derived vector quantity. Its
direction is same as the direction of velocity. The unit of momentum is N.sec or Kg .m /sec. And dimension
is [ M L-1 T-1 ]
The magnitude of a linear momentum is, p = m v
Momentum in terms of second law of motion:
Consider an object of mass “m” is moving with initial velocity “vi” has,
Initial momentum = m vi
After “t” seconds velocity becomes vf,
and, final momentum becomes = m vf
Hence, the change of momentum in “t” sec. = m vf – m vi
m v f - m vi
The of change of momentum in one second =
t
m  v f - vi 
The of change of momentum in one second =
t
v
Rate of change of momentum = m  
t
Therefore ,
Rate of change of momentum = m a
Hence ,
Rate of change of momentum = F
mv
p
= [ force ] =
= Rate of change of momentum
t
t
This equation is for “the second law of motion in terms of momentum” that

The rate of change of the linear momentum is equal to the net force acting on the
body, is the second law of motion.
19. Impulsive force and Impulse:
Impulsive force:
 he rate of change of momentum is called “Impulsive force”.
Its dimension is  MLT -2  .When maximum force applied for very short time interval on to mass then,
m v f - m vi
t
Impulsive Force = Rate of change of momentum
Fmax =
Impulse:
 The product between maximum force and short interval of time is called “Impulse”.
Its dimension is  MLT -1 
m vf - m vi
Fmax =
t
( Fmax  t ) = mvf - mvi
Impulse = change of momentum
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
12-1-Ch.3
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“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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20.  Law of conservation of momentum

“Total momentum before collision is equal to total momentum after collision of the
isolated system remains conserved”.
Explanation:
Consider two unequal masses “m1” and “m2” are moving with initial velocities “U1,” and “U2” respectively along
straight line in the same direction ( where U1 > U2). The total momentum before the head-on collision is (m1 U1+ m2 U2 ).The
collision takes place in time “t” seconds, when the mass “m1” collides with other mass “m2”. After this time the final velocities of
the masses become “V1” and “V2”. The total momentum after collision become ( m1 V1 + m2 V2 ). According to the second law of
motion,
m1V1 - m1 U1
F=
For the mass “m1”
t
m 2 V2 - m 2 U 2
F=
And,
For the mass “m2”.
t
According third law of motion, the force by mass “m2” on to mass “m1 is equal and
opposite in the direction.
Hence.
-Faction  Freation
 m V - m 2 U 2   m1V1 - m1 U1 
- 2 2
 = 

t
t

  m2 V2 - m2 U2  =  m1V1 - m1 U1 
- m2 V2 + m2 U2  m1V1 - m1 U1
m1U1 + m2 U2 = m1V1 + m2 V2 , This is Law of conservation of momentum
Total initial momentum = Total final momentum.
This shows that, whenever two or more particles in an isolated system interact, the total momentum
of the system remains constant. It is known as “Law of conservation of momentum”.
21.Elastic and Inelastic collision: 
Elastic collision: 

Total momentum before collision is equal to the total momentum after collision and
total kinetic energy before collision is equal to the total kinetic energy after collision.
It is called “Elastic collision”.
m1U1 + m2 U2 = m1V1 + m2 V2
1
1
1
1
m1U12 + m 2 U 22 = m1V12 + m 2 V22
And,
2
2
2
2
Inelastic collision: 

Total momentum before collision is equal to the total momentum after collision and
total kinetic energy before collision does not equal to the total kinetic energy after collision. It is
known as “Inelastic collision”.
m1U1 + m2 U2 = m1V1 + m2 V2
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
13-1-Ch.3
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“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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1
1
1
1
m1U12 + m 2 U 22 
m1V12 + m 2 V22
2
2
2
2
22. Calculation of final velocities of two unequal masses after elastic collision: 
Consider two unequal masses m1 and m2 are moving with initial velocities U1 and U2
respectively, ( U1 > U2 ) in the same direction, on one dimension . The masses undergo an elastic head-on collision, in this case,
both momentum and kinetic energy are conserved. Therefore, after the elastic collision the velocities of masses become V 1 and
V2. According to the law of conservation of momentum,
m1U1 + m2 U2 = m1V1 + m2 V2
m1U1 - m1V1 = + m2 V2 - m2 U2
m1  U1 - V1  = + m2  V2 - U2  - - - - - - - - ► eq. 1
According to the law of conservation of kinetic energy,
1
1
1
1
m1 U12 + m 2 U 22 = m1 V12 + m 2 V22
2
2
2
2
1
1
1
1
m1 U12 - m1 V12 = + m 2 V22  m 2 U 22
2
2
2
2
1
1
m1  U12 - V12  = + m 2  V22 - U 22 
2
2
2
2
m1  U1 - V1  = m 2  V22 - U 22  - - - -- - - - ►eq. 2
Divide equation # 2 by equation #1, we get,
m1 ( U12 - V12 )
m2 ( V22 - U 22 )
=
m1 ( U1 - V1 )
m 2 ( V2 - U 2 )
( U1 - V1 ) ( U1 + V1 )
(V - U 2 ) ( V2 + U 2 )
= 2
( U1 -V1 )
( V2 - U 2 )
( U1 + V1 ) = ( V2 + U2 )
- - - - - - - - ►eq. 3
From equation # 3 we get,
- - - - - - - - ►eq. a
V1 = V2 + U2 - U1
And from equation # 3 we get, ( U1 + V1 - U2 ) = V2
- - - - - - - - ►eq. b
By putting equation # (b) in equation # 1,we get,
m1 ( U1 - V1 ) = m2 [( U1 + V1 - U 2 ) - U 2 ]
m1 U1 - m1 V1 = m2 U1 + m2 V1 - m2 U2 - m2 U2
m1 U1 - m1 V1 = m2 U1 + m2 V1 - 2m2 U2
m1 U1 - m2 U1 + 2 m2 U2 = m1 V1 + m2 V1
U1 ( m1 - m2 ) + 2 m2 U2 = V1 ( m1 + m2 )
U1 ( m1 - m 2 ) + 2 m 2 U 2
= V1
( m1 + m 2 )
FIRST YEAR
CHAPTER 3
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MOTION
14-1-Ch.3
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“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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( m1 - m 2 )
2 m2
V1 =
U1 
U2
( m1 + m 2 )
( m1 + m 2 )
By putting equation # (a) in equation # 1 we get,
m1 [ U1 - (V2 + U2 - U1 )] = m2 ( V2 - U 2 )
m1 U1 - m1 V2 - m1 U2 + m1 U1 = m2 V2 - m2 U2
2m1 U1 + m2 U2 - m1 U2 = m1 V2 + m2 V2
2 m1 U1 + U2 ( m2 - m1 ) = V2 ( m1 + m2 )
2 m1U1 +U 2 ( m 2 -m1 )
= V2
( m1 + m 2 )
2 m1
( m 2 -m1 )
V2 =
U1 
U2
( m1 + m 2 )
( m1 + m 2 )
Following are the special cases of elastic collision on one dimension.
Case 1:
Let, m1 = m2 = m. The masses m1 and m2 have initial velocities U1 and U2 respectively. After the collision the final
velocities become,
U ( m1 - m 2 ) + 2 m 2 U 2
V1 = 1
( m1 + m 2 )
U ( m - m ) + 2 mU 2
V1 = 1
(m+m)
U ( 0 ) + 2 mU 2
V1 = 1
( 2m )
2 mU 2
V1 =
( 2m )
V1 =U 2
2 m1 U1 + U 2 ( m 2 - m1 )
V2 =
( m1 + m 2 )
2 mU1 + U 2 ( m - m )
V2 =
(m+m)
2 mU1 + U 2 ( 0 )
V2 =
(m+m)
2 mU1
V2 =
(2 m )
V2 = U1
Case 2:
FIRST YEAR
CHAPTER 3
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Let, m1 = m2 = m. A mass m1 is moving with velocity U1, other mass m₂ is in the state of rest, say U2 = 0.
After the collision the final velocities become,
U ( m1 - m 2 ) + 2 m 2 U 2
V1 = 1
( m1 + m 2 )
U1 ( m - m ) + 2 m  0
(m+m)
U1 (0 )
V1 =
(2 m )
V1 = 0
2 m1 U1 + U 2 ( m 2 - m1 )
V2 =
( m1 + m 2 )
2 m U1 + 0 ( m - m)
V2 =
( m + m)
2 m U1
V2 =
 2 m
V1 =
V2 = U1
Case 3:
Let, mass m1  m2 , say m1  0 and moving with U1. The larger mass m2 = m is in the state of rest, say U2 = 0. After
the collision the final velocities become,
U (m - m 2 ) + 2 m 2 U 2
V1 = 1 1
( m1 + m 2 )
U1 (0 - m ) + 2 m  0 
(0+m)
V1 = - U1
2 m1 U1 + U 2 ( m 2 - m1 )
V2 =
( m1 + m 2 )
V1 =
V2 =
2  0  U1 + 0 ( m - 0 )
(0+m)
0
m
V2 = 0
V2 =
Case 4:
FIRST YEAR
CHAPTER 3
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MOTION
16-1-Ch.3
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“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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Let, mass m1m2 ( say m1= m ) moving with U1.And smaller mass m2  0 , is in the state of rest,
say U2 = 0. After the collision the final velocities become,
U ( m1 - m 2 ) + 2 m1 U 2
V1 = 1
( m1 + m 2 )
U1 ( m - 0 ) + 2 m  0
(m+0)
U (m)
V1 = 1
(m)
V1 = U1
2 m1 U1 + U 2 ( m 2 - m1 )
V2 =
( m1 + m 2 )
2 m U1 + 0 ( 0 - m)
V2 =
(m+0)
2 m U1 + 0
V2 =
(m)
V2 = 2U1
V1 =
Equations.
1. S = vt
2. a =
v
t
3. F = m a
4. vf = vi + g t
5. s = vi t +
1 2
at
2
1 2
mv
p
gt 9.
= [ force ] =
= Rate of change of momentum
2
t
t
U ( m1 - m 2 ) + 2 m 2 U 2
2 m1U1 +U 2 ( m 2 -m1 )
= V1
= V2
10. F =  R
11. 1
12
( m1 + m 2 )
( m1 + m 2 )
2 m1m2g
13. m1U1 + m2 U2 = m1V1 + m2 V2
14. ( Fmax  t ) = mvf - mvi 15. Faction = - Freaction
16. T =
 m1 + m2 
6. 2as = vf2 - vi2 7. vf = vi + g t 8. h = vi t +
g  m1 - m 2 
 mm g 
f 
T=  1 2
20. g sinθ     a 21. p = m v

 m1 + m 2 
m
  m1 + m 2  
F
22. g sinθ = a
23. f = 6   r v
24. μ =
25. Area = π r 2
26. Circumference = 2 π r
R
27 Latrecal surface area = 2 π r L 28. Latrecal surface volume = π r 2 L
29. Surface area = 4 π r 2
4
30. Volume = π r 3 31. Area = L B = Lw + B h 32. Area = 2  Lh+ Lw + hw 33. Volume= L B w
3
17. a =
18. a =
m1 g
 m1 +m2 
19.
Dimensions.
FIRST YEAR
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MOTION
17-1-Ch.3
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“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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PHYSICAL QUANTITY & SYMBOL
DIMENSION
Distance or displacement d or s
Speed or velocity
d
t
v
Acceleration
Force or impulsive force F =
Weight
W
Δp
= ma
t
mg
Mass
m
Tension in string
T=W
Momentum or impulse F t
p
Fluid friction
f
Density

Pressure
p
6πηrv
mv
m s-2
 M   LT -2  =  MLT -2 
kg.ms-2 = Newton
 M   LT -2  =  MLT -2 
 M
 M   LT -2  =  MLT -2 
 M   LT -1  = MLT -1 
kg.ms-2 = Newton
kg
kg.ms-2 = Newton
kg.ms-1 = N.s
kg.m-1.s-1
kg.ms-2 = Newton
kg.m-3

 L3  
 MLT -2 
  ML-1T -2 
2
 L 
 L L =  L2 
F
A
kg.m-1.s-2 = N.m-2 = Pascal
m2
 L L L = L3 
V lbh
Acceleration due to gravity
Coefficient of friction 
Force density
m s-1
 M  = ML-3 
m
V
Area A lb
Volume
 L    LT -1 
T  
 ML-1T -1 
 ML-1T -1   L   LT -1  =  MLT -2 

Viscosity
m
 LT -1 
  LT -2 
T
 
v
t
a
UNIT
[L]
g
F
R
m3
 MLT -2 
=  LT -2 
M
W
m
m.s-2
 MLT -2 
= No dimension
 MLT -2 
no unit
 MLT -2 
=  ML-2T -2 
3
 L 
F
V
Relative density
mass of substance
mass of water
FIRST YEAR
CHAPTER 3
 M  = no dimension
M
2010 – 2011
MOTION
kg.m-2.s-2 = N.m-3
No unit
18-1-Ch.3
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1
1
=  M -1L3 
Specific volume
kg-1.m3
-3
 ML 
ρ
 ML0 T -2 
Surface tension
kg.s-2.
Short questions and answers
Q. No.1:
can a body moving at a constant speed have acceleration?
Answer:
when a body is moving in a circular path with a constant speed can have acceleration. In a circular path the direction of
speed continuously changed but magnitude remains constant.
Q. No.2:
What is gravity? Explain the effect on the motion of free falling bodies.
Answer:
We know that earth attract every body to ward its center with a force, such force is called gravity.
Hence, earth experiences an attractive force on every free falling bodies towards it center. Free falling bodies have zero
initial velocity and positive acceleration due to gravity. And when thrown vertically upward freely than final velocity become
zero and negative acceleration due gravity. These are the effect on free falling bodies.
Q. No.3:
If a ball is thrown vertically upwards and the acceleration on it is neg 9.8 due to gravity will the sign change when the ball changes
direction to fall back down thus giving an acceleration of 9.8?
Answer:
Yes. On the way up, negative acceleration is taking place because the ball is moving up and gravity is acting in the opposite
direction. On the way back down, acceleration is positive, and the object starts at rest. Yes. On the way up, negative
acceleration is taking place because the ball is moving up and gravity is acting in the opposite direction. On the way back
down, acceleration is positive, and the object starts at rest.
Q. No.4:
What is Inertia?
Answer:
The Inertia is a tendency of a body to remain in its original state. A body is in the state of rest will not change its state
by it self or a body in the state of motion will not come to rest by itself. This is due to inertia.
Q. No.5:
Why the gun recoils, when a shell is fired from the gun?
Answer:
According to the third law of motion, every reaction is equal in magnitude but opposite in direction of action .So
that gun applied action in forward direction and bullet experienced reaction in opposite direction. Thus, the gun recoils, when
a shell is fired from the gun.
Q. No.6:
Define elastic collision and inelastic collision.
Answer:
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
19-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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Elastic collision
The Collision in which momentum and kinetics energy remain conserved is called elastic
collision.
1
1
1
1
m1U1 + m2 U2 = m1V1 + m2 V2 And m1U12 + m 2 U 22 = m1V12 + m 2 V22
2
2
2
2
Inelastic collision
The collision in which momentum remains conserved and kinetic energy does not remains conserved
.Such type of collision is called inelastic collision.
1
1
1
1
m1V12 + m 2 V22
m1U1 + m2 U2 = m1V1 + m2 V2 And m1U12 + m 2 U 22 
2
2
2
2
Q. No.7:
Why moving bicycle is easy to stop but moving car is difficult to stop?
Answer:
Because, greater the momentum greater the mass or velocity, thus moving bicycle has smaller moment um than
moving car. So that moving bicycle is easy to stop but moving car is difficult to stop.
Q. No.8:
What is the physical significance of momentum?
Answer:
The motion of moving body is the physical significance of momentum.
Q. No 9:
What do you know about fluid friction?
Answer:
The fluid friction is made to flow around a stationary object then friction produces itself. Such friction is involved in
the ships through water and automobile through air. F= 6 π η r v
Q. No.10:
Find the mass of a body whose weight is 1960N.
Answer:
W
We know that, W = mg
 m=
g
1960 N
m=

m = 200 kg
9.8 m sec-1
Q. No.11:
Define a) Impulse b) law of conservation of momentum c) Impulsive force.
Answer:
a) Impulse:
The product between maximum force and short time interval is called “impulse”. F max t = mvf - mvi
Impulse = Change of momentum
b) Law of conservation of momentum:
Total initial momentum before collision is equal to the total final momentum after collision, is called law of conservation of
momentum.
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
20-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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M U1 + m U2 = M v1 + m v2
c) Impulsive force:
The maximum force applied for very short time interval, is called impulsive force.Fmax = m vf- m vi
t
Impulsive force = Rate of change of momentum
Q. No.12:
A block rests on an inclined plane. What forces act on it? Draw force diagram.
Answer:
A block rests on an inclined plane under first condition of equilibrium. Fx = 0 and  FY = 0
Three forces are acting on to a body. One of them is the “weight” of a body, second one is the normal reaction force applied
by inclined plane and third one is the “force of friction” opposes the motion of a body.
Q. #10:
Differentiate between the mass and weight.
Answer:
MASS
WEIGHT
1. It is a quantity of a matter.
1.
It is not a quantity of matter
2. It is fundamental quantity
2. It is derived quantity
In the metric system.
in metric system.
3. Its units are kilogram and
3. Its unit is Newton and dyne
gram in metric system.
in metric system.
4. It is measured by physical balance.
4. It is measured by spring balance.
5. m = W/ g
5. W = m g
6. It is not a pull of gravity.
6. It is a pull of gravity.
7. It remains constant every where.
7. It does not remain constant everywhere.
8. It is fundamental quantity
8. It is derived quantity.
Q. No.13:
Define force and give its units.
Answer:
The force is an agent of pushing or pulling of any object. It depends on to mass of an object and accele4ation
produced in it. Thus, F = m a Its unit is Newton and dyne in metric system.
Q. No.14:
Define coefficient of friction.
Answer:
The ratio between normal reaction force applied by the surface and limiting force is called coefficient of friction. =
F/R
Q. No.15:
Define static and kinetic friction.
Answer:
Friction is divided into two types-static and kinetic. These are represented by Fs, for static friction, and Fk, for kinetic friction. Static
friction occurs when the body is not moving with respect to the surface. It is the force which makes it difficult to start something
moving. On the other hand, kinetic friction occurs when the body is sliding over the surface. Rolling objects also experience friction.
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
21-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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This is the force which causes objects to slow down and eventually stop. Friction is usually approximated as
being proportional to the normal force. The proportionality constant is called the coefficient of static or kinetic
friction. The coefficient is represented as µs for static friction, and µk for kinetic friction; the numerical value
of µ depends on the nature of the surface with which the body is in contact.
Q. No.16:
What is SI unit of momentum?
Answer:
The unit of momentum in S.I. system is N.sec.
Q. No.17:
What do you mean by an isolated system?
Answer:
The isolated system means, a system having distinct boundaries through which no transformation of matter and energy.
Q. No.18:
It is well known that balancing a bicycle standing still is almost impossible, while on a rolling bike it is quite easy. Why?
Answer:
The natural tendency is to lean to the right, to counter balance the lean with your weight. But in moving the top of your
body to the right, by Newton's 3rd law you are actually pushing the bike to lean more to the left. May be you should lean to the left
and push the bike back? It might work for a fraction of a second, but now you are really out of balance. circle of action and
reaction.
Why is uniform circular motion called accelerated motion? [Improve]
if an object moves along a circular path, the only change in its velocity is due to the change in the direction of the
motion. The motion of the object moving along the circular path is, which is a uniform circular motion, is therefore
an accelerated motion.
What is the difference between uniform motion and uniformly accelerated motion?
Uniform motion is constant acceleration non uniform is not.
What is uniformly accelerating linear motion?
Linear motion
Motion implies momentum, which implies velocity. Linear implies a straight line. Accelerating implies changing
velocity. And uniform implies constancy.
So, when an object moves in a straight line and accelerates at a constant rate, you have uniformly accelerating linear
motion.
Describe the term inertia with respect to motion? Every mass has inertia.When an inertial mass is in motion, it tends to
continue to be at it's state of motion obeying newton's first law of motion.The law states that every body in this universe
continues to be at the state of rest or motion until and unless acted by an external force.We experience inertia of motion
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
22-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
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when we are riding a vehicle in motion.When the vehicle tries to stop suddenly, we are jerked
forward. This jerking is due to inertia of motion as our bodies try to continue to be at the state of
motion in accordance to newton's first law.
Old papers questions
The Bicycle
balancing a bicycle standing still is almost impossible, while on a rolling bike it is quite easy. Why?
Different principles are at work in each case. Suppose you sit on a bike that stands still, and find it is leaning to the
left. What do you do? The natural tendency is to lean to the right, to counter balance the lean with your weight. But
in moving the top of your body to the right, by Newton's 3rd law you are actually pushing the bike to lean more to
the left. May be you should lean to the left and push the bike back? It might work for a fraction of a second, but now
you are really out of balance. No way!
On a rolling bike, balance is kept by a completely different mechanism. By slightly turning the handle bars right or
left, you impart some of the rotation of the front wheel ("angular momentum") to rotate the bike around its long axis,
the direction in which it rolls. That way the rider can counteract any tendency of the bike to topple to one side or the
other, without getting into the vicious circle of action and reaction.
To discourage thieves, some bikes contain a lock which clamps the handlebars in a fixed position. When such a
bike is locked in the forward-facing direction, it can be rolled by a walking person, but it cannot be ridden because it
cannot be balanced.
Galileo challenged Aristotelian notions about motion by performing experiments.
Newton's first law of motion (Galileo's Principle of Inertia) describes what Galileo had discovered about inertia in his
"thought experiments," using inductive reasoning.
A net force is the resultant of all forces acting on an object. Equilibrium exists if the net force is zero. (There must
also be no resultant torque.)
If no external unbalanced force acts on an object, its velocity will remain constant (i.e., it will remain at rest if it was
initially at rest, or continue moving in a straight line at a constant speed, if it was initially doing so).
If all of the forces acting on an object cancel one another, the resultant vector is zero and no unbalanced force exists.
The object is in equilibrium.
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
23-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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CELL # 0333-2602675
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An object at rest on a table has its weight opposed by a normal force acting on the object by the
table. (Other examples of objects in static equilibrium can be used to illustrate this concept.)
If an object is moving at a constant velocity (including the possibility of being at rest) one can
conclude that all of the forces acting on the object must be balanced. The net force is zero.
Many practical applications of Newton's first law are evident in common occurrences.
Inertia can be used to illustrate how objects tend to resist their state of rest or motion.
When analyzing situations involving more than one force acting on an object, it is extremely useful to represent the
situation using free body diagrams. Vector addition can be used to determine the net force.
When a net force acts on an object, it accelerates in the direction of the net force. (Newton's second law)
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
24-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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A man may imagine things that are false, but he can only understand things that are true, for if the things
be false, the apprehension of them is not understanding.
Isaac Newton
Errors are not in the art but in the artificers.
Isaac Newton
I can calculate the motion of heavenly bodies, but not the madness of people.
Isaac Newton
I was like a boy playing on the sea-shore, and diverting myself now and then finding a smoother pebble or a
prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.
Isaac Newton
If I have done the public any service, it is due to my patient thought.
Isaac Newton
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
25-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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If I have seen further than others, it is by standing upon the shoulders of giants.
Isaac Newton
It is the weight, not numbers of experiments that is to be regarded.
Isaac Newton
Tact is the art of making a point without making an enemy.
Isaac Newton
To every action there is always opposed an equal reaction.
Isaac
Newton
To me there has never been a higher source of earthly honor or distinction than that connected with
advances in science.
Isaac Newton
To myself I am only a child playing on the beach, while vast oceans of truth lie undiscovered before me.
Isaac Newton
We are to admit no more causes of natural things than such as are both true and sufficient to explain their
appearances.
Isaac Newton
We build too many walls and not enough bridges.
Isaac Newton
FIRST YEAR
CHAPTER 3
2010 – 2011
MOTION
26-1-Ch.3
It’s Understanding, It’s Responsibility, It‘s Desire, It’s Reality, a Better shade, be share
“This most beautiful system (The Universe) could only proceed from the dominion of an intelligent and powerful Being.
Heart collection, mind satisfaction, best time for carrier, hard working, try for unlimited Education
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