Fundamentals of Physics Extended (10th Edition)

Published by Wiley
ISBN 10: 1-11823-072-8
ISBN 13: 978-1-11823-072-5

Chapter 7 - Kinetic Energy and Work - Problems - Page 174: 57a

Answer

$F = 798~N$

Work Step by Step

In the final position, we can find the angle $\theta$ the rope makes with the vertical: $sin~\theta = \frac{4.00~m}{12.0~m}$ $\theta = sin^{-1}(\frac{4.00~m}{12.0~m})$ $\theta = 19.5^{\circ}$ The vertical component of the tension in the rope is equal in magnitude to the gravitational force on the crate. We can find the force of tension $F_T$ in the rope: $F_T~cos~\theta = mg$ $F_T = \frac{mg}{cos~\theta}$ $F_T = \frac{(230~kg)(9.8~m/s^2)}{cos~19.5^{\circ}}$ $F_T = 2391~N$ In the final position, the force $F$ is equal in magnitude to the horizontal component of the tension in the rope. We can find the magnitude of $F$: $F = F_T~sin~\theta$ $F = (2391~N)~sin~19.5^{\circ}$ $F = 798~N$
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.