Ch-8 Motion: Difference Between Uniform and Non Uniform Motion

CH-8 MOTION
Difference between uniform and non uniform motion

Uniform Motion Non-Uniform Motion
If any object covers equal distance in If any object covers unequal distance
equal interval of time then it is known in equal interval of time then it is
as uniform motion known as non-uniform motion
Distance time graph is a straight line Distance-time graph is a curved line
Acceleration is zero Acceleration is not zero
It is constant It is not constant
Difference between distance and displacement

distance Displacement
The distance travelled by the body is When a body moves from one point to
the actual length covered by a body another then the shortest distance
irrespective of the direction in which between initial and the final, alongwith
the body travelled. direction, is known as displacement.
Distance travelled refers to the actual Displacement refers to the straight
length of the indirect path. between initial and the final position.
Distance is a scalar quantity Displacement is a vector quantity
Distance cannot be zero Displacement can be zero.
Ch-8
Explain first, second and third law of motion of newton.
First law of motion
A body at rest will remain at rest and a body in motion will remain in motion in a straight line with a
uniform motion, unless it is compelled by an external form to change its state of rest or of uniform
motion
Example- suppose a book is lying on the table, it is at rest, it cannot change its state of rest until
someone move with their hand or an external force is applied on the book. That is why when we lift
the book and its position is changed by an external force.
Second law of motion

The rate of change of momentum of an object is directly proportional to the applied force, and takes
place in the direction in which the force acts.
Derivation
change∈momentum
f∝
time taken
f∝ p 2− p 1
mv−mu
F∝
t
m( v−u)
F∝
t
F∝ ma
v-u/t
We apply k to remove directly proportional
F = kma
k=1
F=ma
Third law of motion

Whenever one body exerts a force on another body, then the second body equal and opposite force
on first body.
Example- When a bullet is fired from a gun then force sending the bullet forward is equal to the
force sending the bullet backword. But due to the high mass of the gun it moves only a little and
gives a backword jerk to the shoulder of the gunman.
Inertia
Inertia is that property of a body due to which it resists in its state of rest or of uniform motion.
Example. a stone has a greater inertia then a football, if a person kicks a stone then the stone will
not move due to its high inertia, but when we kick a football then it will move a long. From this we
can conclude that stone high inertia to resist a change in its state.
Momentum
It is a vector quantity
SI unit is kg.m/s
Definition- momentum of a body is defined as product of its mass and velocity.
It formulae is p=mv
P= momentum
m= mass
v= velocity
conservation of momentum
when two(or more) body act upon each other then their momentum will remain constant provided
no external force are acting
formulae- m1u1 + m2u2 = m1v1 + m2v2

CH 10 GRAVITATION
Universal law of gravitation
Universal law of gravitation states that every object in the universe attract every other object with a
force is directly proportional to the product of their mass and inversely proportional to the square of
their distance travelled.
Derivation
f ∝(m 1)( m2)

1
f∝ 2
d ¿
¿
(m1)(m2)
f∝
d2 ¿
¿
(m1)(m2)
f =G 2
d ¿
¿
Difference between mass and weight

mass Weight
Mass of a body of quantity of matter(or Weight of a body is force of attraction
atoms) in it. toward the centre of the earth.
Mass is constant and does not changes Weight is not constant and changes
from place to place from place to place
It is a scalar quantity It is a vector quantity
Its SI unit is kilogram Its SI unit is Newton
It cannot be zero It can be zero . For example, in inter
interplanetary space where g=0, the
weight of an object becomes zero.
CH -11 WORK AND ENERGY

define work and write its formulae
work done in moving a body is equal to the production of force exerted on the body and the
distance moved by the body in direction of force
formulae:
work = Force x displacement
W=Fs
W=work
F=force
s= displacement
Kinetic energy
Energy of a body due to its motion is known as kinetic energy.
Potential energy
Energy of a body due to its position or change in shape is known as potential energy.
Derivation
Potential energy of a body is due to its height above the surface of the earth is equal to the word
done on the body against gravitational force.
To found out potential energy of a body lying above the surface of earth at certain height, all that we
have to do is to find out the word in taking the body to that height.
Suppose a body of mass m raised to height h above the surface of the earth. The force acting on the
body is gravitational pull of the earth m x g which acts in the downward direction. To lift the body
above the surface of the earth we have to do work against the gravity.
W=mgh
The work is stored up the body as potential energy
P.E=mgh
Difference between kinetic and potential energy

Potential energy Kinetic energy
Energy of a body due to its position or Energy of a body due to its motion is
change in shape is known as potential known as kinetic energy
energy
It can only be converted in the kinetic It can be converted into any form
energy
It does not depend on speed of a body It depend on speed of a body
E.g- book lying on table, flower, car has E.g- flowing water, moving car, running
been haised into some height,etc. cat ,etc.
When work is said to be done

Work is said to be done when force causes displacement of a body in the direction of the applied
force
Conditions for work done
1. A force must act on the body and it must cause the displacement
2. The object must be displaced.

Ch-8 Motion: Difference Between Uniform and Non Uniform Motion

Uploaded by

Copyright:

Available Formats

Ch-8 Motion: Difference Between Uniform and Non Uniform Motion

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Ch-8 Motion: Difference Between Uniform and Non Uniform Motion

Uploaded by

Copyright:

Available Formats

CH-8 MOTION

Difference between uniform and non uniform motion

Difference between distance and displacement

Second law of motion

We apply k to remove directly proportional

Third law of motion

Definition- momentum of a body is defined as product of its mass and velocity.

formulae- m1u1 + m2u2 = m1v1 + m2v2

f ∝(m 1)( m2)

Difference between mass and weight

CH -11 WORK AND ENERGY

work = Force x displacement

The work is stored up the body as potential energy

Difference between kinetic and potential energy

When work is said to be done

Conditions for work done

You might also like