Question

Question: Give brief explanations for your answers to each of the following questions: (a) You hold a 1 kg book in your hand for 1 min. How much work do you do on the book? (b) In a circular pendulum how much work is done by the string on the mass in one revolution? (c)For a mass oscillating horizontally on a spring, how much work is done by the spring on the mass in one complete cycle? In a half cycle?

Short answer

Answer

1. Work done on the book is Zero
2. Work done by the string on the mass in one revolution is Zero.
3. Work done by the spring on the mass in one complete cycle and in a half cycle is Zero.

Step-by-step solution

Definition of work

Work is said to be done when an object is displaced from its actually position when an external force is applied on it. The work done due to the force is given by $W=\overrightarrow{F}$$.∆\overrightarrow{r}$where $W$is the work done, $\overrightarrow{F}$is the external force and is the displacement.