Suppose two coolies , Coolie A and Coolie B lifts a same load on a roof of bus in 1 minute and 2 minutes respectively , they both do same work.

My confusion is that :

We know , Work = Force × Displacement

Here the distance remains same from ground to roof.

But my question is that how the force remains same since Coolie A takes less time than coolie B then force of coolie A must be less than coolie B hence work should be different. Then how work done is same?

Thank you for the opportunity to help you with your question!

A force is any interaction that tends to change the motion of an object. In other words, a force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. and this means that they will both require the same force for lifting the load.

Work done=Force*displacement, displacement is the height of lifting the load and hence is also the same regardless of the time spent lifting the load.

Work hence will be the same for both Coolie

Please let me know if you need any clarification. I'm always happy to answer your questions.

My confusion is still not clear. See you say force = mass × acceleration. Now the first coolie A takes 1 minute that means the acceleration was more than of Coolie B who took 2 minutes. Right ? Then force for coolie A is greater than of coolie B right? Then how ?

Jul 16th, 2015

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