Question

In which of the following cases, is work being done?

• A. A man pushing a wall
• B. A coolie standing with a load of $12kgf$ on his head
• C. A boy climbing up a staircase
• D. None of these

Answer 1

The correct option is C A boy climbing up a staircase

In option A, while man is pushing wall,it will not have any displacement and hence, he is not doing any work.In option B, same situation and no work is done as coolie is not moving.In option C, angle between force and displacement is not ${90}^0$ and it has displacement.Hence, option C is the correct answer.