The presentation is based on class 7th physics ICSE book. Hope you can learn sometheing from it.

1. Motion

2.  Translatory motion- Linear motion, also called rectilinear motion, is one-dimensional
motion along a straight line. Eg- a car moving on a straight road.
 Circular motion- circular motion is a movement of an object along the circumference of
a circle or rotation along a circular path. Eg- whirling a stone tied to a string is an
example of circular motion.
 Rotatory motion- circular motion, is physical motion that happens when an object rotates
or spins on its axis. Eg- Ceiling Fan.
 Oscillatory motion- Oscillatory motion is defined as the to and fro motion of the body
about its fixed position. Oscillatory motion is a type of periodic motion. Examples
of oscillatory motion are vibrating strings, swinging of the swing etc.
 Periodic motion- Periodic motion is motion repeated in equal intervals of time. Eg- by a
rocking chair, a bouncing ball, a swing in motion, the Earth in its orbit around the Sun.
TYPES OF MOTION

3.  Non-periodic motion- The motion which does not repeat itself after regular interval
of time is called non-periodic motion. Eg- a footballer running on a field,
application of brakes in a moving vehicle.
 Multiple motion- When a body possesses more than one simple motion, it is called
a multiple motion. Example: You are travelling by a train. Your wrist watch is also
sharing the linear motion of the train. But the hands of the watch are also
undergoing rotational motion. Thus they have 2 kinds of motion.
 Rolling motion- Rolling is a type of motion that combines rotation and translation
of that object with respect to a such that, if ideal conditions exist, the two are in
contact with each other without sliding.
 Random motion- Random motion is defined as the motion of an object with no
specific path but undergoes sudden change in its motion. Eg- of random motion is
flying of kite.

4.  Uniform motion- When a body covers equal distances in a straight line, equal intervals of
time are called uniform motion. Example: a car moving at 20km/h in a straight line.
 Non-Uniform motion- When a body covers unequal distance in equal intervals of time in a
straight line is called non-uniform Example : spinning wheel.
Simple pendulum
A simple pendulum consists of a small metal ball (called bob) suspended by a long thread
from a rigid support, such that the bob is free to swing back and forth. A pendulum completes
every swing (or every oscillation) in exactly the same time, provided its length is kept constant.
 Oscillation- The motion of pendulum starting from one extreme end to another extreme end
and back to the first extreme end is called one oscillation. Similarly, the motion of a simple
pendulum from its mean position to extreme left and extreme right and back to the mean
position is called one oscillation.
 Amplitude- The amplitude of a simple pendulum is the maximum distance moved by the
bob on either side of the mean position. It is thus one-half the distance that the bob traverses
in moving from one side to the other.

5.  Time period-The time taken to complete one oscillation is known
as the time period of the pendulum.
 Frequency- the number of complete oscillations executed by the
bob in one second is called its frequency. It is
denoted by f. its unit is hertz (Hz)
1hertz= 1 cycle per second
The relation of time period and frequency is written as:
Frequency= 1/time period; v=1/T
Time Period= 1/frequency; T=1/v
Factors affecting the time period of a simple pendulum
 The time period of a simple pendulum is neither affected by the
mass of the bob nor by the amplitude of oscillation. However it is
affected by the length of the pendulum.
 Law of mass- the time taken by the pendulum for one oscillation
does not change with the change in mass of the pendulum.
 Nature of the material of the bob- it is independent of the nature of
the material.
 Law of amplitude- the time period of a simple pendulum is
independent of the amplitude of the amplitude of oscillation.

6.  Law of length- the time period of a simple pendulum is independent of its amplitude of
oscillation.
 Law of length- the time period of a simple pendulum is directly proportional to the square
root of its length.
 Law of gravity- the time period of a simple pendulum at a given place is inversely
proportional to the square root of the acceleration due to gravity at that place.

7. THANK YOU