Force is any influence that causes an object to change its motion, shape, or state of rest. There are different types of forces, including contact forces that require touching an object, like pushing a table. Balanced forces occur when multiple forces cancel each other out, while unbalanced forces result in a net force that changes the motion of an object. Internal forces cause acceleration within an object due to its mass, while external forces interact with the environment and are needed to move objects.

6. FORCE
Force is an influence which tends to set
a stationary body in motion or which tends
to change the speed and direction of a
moving body or which tends to change the
shape of a body
eg: The table moves when force is applied
Batsman strike the ball
Cart moves when force will apply

8. A force that can be applied only
when it is in contact with an object is
called contact force
Examples;
The table moves when force will apply
Cart moves when force will apply
Batsman strike the ball

10. BALANCED FORCE

11. UNBALANCED FORCE
When a number of forces act on a
body and the resultant of these
force is not zero then the force are
said to be un balanced force
Examples;
Two people push a table with
different forces

12. INTERNAL FORCE
Internal force is whatever causes an object with
mass to accelerate or move. This force is equal
to the product of the mass of the object plus its
rate of acceleration
EXTERNAL FORCE
External force act an object as a result of
interaction with the environment surrounding it.
Example;
We can lift the chair by standing on the floor ,
an external force is necessary to move an
object.