Question

A body of mass 20 kg is displaced by a distance of 5 m in the direction of the force. What is the work done on the body? ​

Answer 1

Explanation:

Work is said to be done when a force applied to an object moves that object. Work done is generally referred to in relation to the force applied while energy is used in reference to other factors such as heat.

Kinetic energy is given by the expression,

(K. E)v = 1/2 mv2

Where,

K. E = Kinetic energy of the object

v = velocity of the object

Kinetic energy when the object was moving with a velocity of 5 m/s

(K. E)5 = 1/2 × 20 × (5)2

(K. E)5 = 250 J

Kinetic energy when the object was moving with a velocity 2 m/s

(K. E)2 = 1 /2 × 20 × (2)2

(K. E)2 = 40 J

Work done = Change in kinetic energy

= 40 J – 250 J

= – 210 J

Therefore, work done = -210 J

Check out the video given below to know more about kinetic and potential energy.