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zero1520
Oct20-04, 07:12 PM
:confused: Ok, I have understood every problem we have done so far except this one,

You are wearing shoes that have a coefficient of friction on rock of 0.70. On how steep a rock slope could you stand without slipping?

So far i have gotten:
Fs=Fparallel=
mu*W*costheta = W*sinTheta
w=mg

but if u cancel weights I got:
mu*costheta = sintheta

Im probably completely wrong, but thats what i got.
Thanks in advance.

Pyrrhus
Oct20-04, 07:17 PM
Similar problem

http://www.physicsforums.com/showthread.php?t=47478

Also btw the slope will be m = \frac{\Delta y}{\Delta x} = tan\theta

zero1520
Oct20-04, 07:22 PM
well i guess my problem is solving the trig cause i simplified to what he got on that similar problem

Doc Al
Oct20-04, 07:22 PM
Looks good to me. The friction force must equal the parallel component of the weight. Good!

Now keep going: \mu cos\theta = sin\theta ==> tan\theta = \mu. Now solve for \theta. (Use your calculator.)

zero1520
Oct20-04, 07:31 PM
ohhh alright i got it, thank you very much