0

I'm sorry that I can only give the question here but I have no idea how to calculate $\mu$. Question is as follows:

A body is projected at $24\text{ft/sec}$ up a rough plane inclined at $\text{tan}^{-1} \frac{7} {24} $ to the horizontal. With what velocity does it return to the point of projection?

Despite several attempts, I have been unable to calculate $\mu$ and therefore can not find retardation or acceleration. I have tried looking at the point where instantaneous velocity is zero but if I take retardation and acceleration as zero at this point then I end up in a bit of a pickle! If anyone can offer any helpful advice/hints then I would be extremely grateful.

GR L
  • 329
  • 1
    Perhaps you are supposed to give an answer that is not a single number, but rather the "return" velocity as a function of $\mu.$ – David K Feb 14 '22 at 14:06
  • I thought so too but solution gives $8\sqrt{5}\text{ft/sec}$. Don't want to appear defeatist but wondering if the question is incomplete. – GR L Feb 14 '22 at 14:12
  • I've just reverse engineered the question using solution to get a value of $\mu=\frac{1} {12} $. Plugging this in gives solution from back of book. Again, I'm left wondering if question is incomplete or if I've missed a slick trick in calculating $\mu$. Many thanks again for any advice. – GR L Feb 14 '22 at 14:29
  • 1
    It sounds like an incomplete question. Either that, or there's an earlier paragraph saying something like "Assume $\mu = 1/12$ in the next several questions." But my bet would be it's just incomplete. – David K Feb 14 '22 at 17:57
  • Thank you very much for taking the time to reply. You're quite right, there is no prior information regarding the value of $\mu$ so I agree that the question must be incomplete. – GR L Feb 14 '22 at 18:26

0 Answers0