Question

How much work is required to hold a 2kg book 2m above the ground?

Answer 1

Given that the mass of the book is m = 2kg.

The height of the book from the ground is h = 2 m.

We have to find the work done.

The formula to calculate work done is

`\begin{gathered} W\text{ = Potential energy} \\ =\text{mgh} \end{gathered}`

Here, g =9.8 m/s^2 is the acceleration due to gravity.

Substituting the values, the work done will be

`\begin{gathered} W=\text{ 2}*9.8*2 \\ =39.2\text{ J} \end{gathered}`

Thus, the work done will be 39.2 J.