Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (3rd Edition)

Published by Pearson
ISBN 10: 0321740904
ISBN 13: 978-0-32174-090-8

Chapter 11 - Work - Exercises and Problems: 33

Answer

The motor pumps 55,000 liters of water in one hour.

Work Step by Step

We can convert the power of the motor to units of watts. $P = (2.0~hp)(746~W/hp)$ $P = 1492~W$ We then find the total energy supplied by the motor in one hour. $E = P~t$ $E = (1492~W)(3600~s)$ $E = 5.37\times 10^6~J$ The energy supplied by the motor will be equal to the change in potential energy of the water. Let $M$ be the mass of the water. $PE = 5.37\times 10^6~J$ $Mgh = 5.37\times 10^6~J$ $M = \frac{5.37\times 10^6~J}{gh}$ $M = \frac{5.37\times 10^6~J}{(9.80~m/s^2)(10~m)}$ $M = 55,000~kg$ Since the density of water is 1.0 kg/liter, the motor pumps 55,000 liters of water in one hour.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.