Engineering Mechanics: Statics & Dynamics (14th Edition)

Published by Pearson
ISBN 10: 0133915425
ISBN 13: 978-0-13391-542-6

Chapter 16 - Planar Kinematics of a Rigid Body - Section 16.3 - Rotation about a Fixed Axis - Problems - Page 331: 5


$\theta=5443rev$ $\omega=740rad/s$ $\alpha=8rad/s^2$

Work Step by Step

We can determine the required number of revolutions, the angular velocity, and the angular acceleration as follows: $\theta=4t^2+20t$ We plug in the known values to obtain: $\theta=4(90)^2+20(90)$ This simplifies to: $\theta=34200rad$ Now we can find the number of revolutions as $\theta=(34200rad)(\frac{1rev}{2\pi rad})=5443rev$ The angular velocity is given as $\omega=\frac{d\theta}{dt}$ $\omega=20+8t=20+8(90)=740rad/s$ and $\alpha=\frac{d\omega}{dt}=8rad/s^2$
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.