Speed = 5 km/m = \(\frac { 5000 }{ 3600 } \) m/s
Time = 15 min = 15 x 60 sec
Distance = Speed x time
=\(\frac { 5000 }{ 3600 } \) x 15 x 60 = 1250 m

A spin dryer removes excess water from clothing by rotating a perforated drum at high speed. The water is thrown out through the holes. The clothes keep moving in a circle because the contact force of the drum provides centripetal force.

(i) The dryer in a washing machine is an example for the application of centrifugal force.
(ii) When we go for a ride in a merry-go-round in amusement parks, we experience an outward pull as merry-go-round rotates about vertical axis. This is due to centrifugal force.

Force acting on a body away from the centre of circular path is called centrifugal force. Thus, centrifugal force is in a direction opposite to the direction of centripetal force. Its magnitude is same as that of centripetal force.

The motion of a stone in circular path with constant speed and continuous change of direction is an accelerated motion. There must be an acceleration acting along the string directed inwards, which makes the stone to move in circular path. This acceleration is known as centripetal acceleration and the force is known as centripetal force.

Acceleration is the rate of change of velocity or it is the change of velocity in unit time.

Speed is the rate of change of distance or the distance travelled in unit time.
Speed = \(\frac { Distance\ travelled }{ time\ taken } \).

An object is said to be in uniform motion if it covers equal distances in equal intervals of time.

Displacement is defined as the change in position of a moving body in a particular direction.

The actual length of the path travelled by a moving body irrespective of the direction is called the distance travelled by the body.

The different types of motions are circular, linear, oscillatory, uniform and random motion.

(i) The body is said to be in the state of rest when it remains in the same position with respect to time.
(ii) The body is said to be in the state of motion, when it continuously changes its position with respect to time.

To balance frictional force by centrifugal force a cyclist leans inwards, so that he can avoid skidding.