Question

a coolie carries a load of 50kg on his head and walks on a level road upto 100m . what is the work done by him?

Answer 1

work done is 0 because since it is perpendicular to the ground and cos90 degree is 0

Answer 2

Given:

Mass of load,m=50 Kg

Distance traveled by coolie=s=100 m

To find:

Work done by coolie

Solution:

We know that

Work done,w=$Fsco\theta$

Where F= Force

s= Displacement

$\theta$=Angle between Force and displacement

We have

$\theta=90^{\circ}$

Because  coolie is perpendicular to the road

Using the formula

Work done,w=$F(100)cos90^{\circ}=0$

Hence, the work done by coolie=0 J