Question

A 2 kg block is on a horizontal surface. A horizontal force is applied by a person to the block to pull it on the surface with an acceleration of 2 m/s. The coefficient of kinetic friction between the box and the surface is 0.3. How much work is done in joules by the person on the block if the block is pulled 50 m? a) 200 joules b) 250 joules c) O joules d) 300 joules e) 500 joules

Answer 1

Answer:

work done = 500 J

option e is correct

Explanation:

given data

mass = 2 kg

acceleration = 2 m/s

coefficient of kinetic friction = 0.3

block D = 50 m

to find out

work

solution

we know that work done is

work done = f × d    ...........1

here f is force and d is block i.e 50 m

so here

force , f - k mg  =ma

f = 2 ( 2 + 0.3 ×10 )

f = 10 N

so from equation 1

work done =  f × d

work done = 10 × 50

work done = 500 J

option e is correct