Chapter 11, Problem 3STP

To determine

To Choose: The correct option.

Answer to Problem 3STP

Option D. $34\text{J}$

Explanation of Solution

Given:

The mass of the book, $m=2.5\text{kg}$

Initial height of the book, $h_i=1.2\text{m}$

Final height of the book, $h_f=2.6\text{m}$

Formula used:

The gravitational potential energy of an object which is at a height $h$ from the surface is given by,

  $PE=mgh$

Calculation:

Using the given values in above, the change in the potential energy of book and Earth system is,

  $\begin{array}{c}\Delta PE=P{E}_f-P{E}_i\\ =mg\left(h_f-h_i\right)\\ =\left(2.5\right)\left(9.8\right)\left(2.6-1.2\right)\\ \approx 34\text{J}\end{array}$

Conclusion:

Thus, the change in the potential energy of book and Earth system is $34\text{J}$ .