Chapter 6, Problem 9RQ

How many joules of potential energy does a 1-N book gain when it is elevated 4m ? When it is elevated 8m ?

To determine

The potential energy does a 1N book gain when it is elevated 4m and 8m .

Answer to Problem 9RQ

The potential energy does a 1N book gain when it is elevated 4m is 4J and for 8m is 8J.

Explanation of Solution

Given info: Weight of the book is 1N , and the elevation of the book is 4m and 8m respectively..

Write the expression for the potential energy.

PE=Wh

Here,

W is the weight of the book

h is the elevation from the ground

Substitute 1N for W and 4m for h in the above expression to get PE .

$\begin{array}{c}PE=1\text{N}\times 4\text{m}\\ =4\text{J}\end{array}$

Substitute for and for in the above expression to get .

$\begin{array}{c}PE=1\text{N}\times 8\text{m}\\ =8\text{J}\end{array}$

Conclusion:

Therefore, the potential energy does a 1N book gain when it is elevated 4m is 4J and for 8m is 8J.