Coefficient of friction on rock of 0.70

[zero1520]

physics help!

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 that's what i got.
Thanks in advance.

 

[Pyrrhus]

Similar problem

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

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

 

[zero1520]

well i guess my problem is solving the trig cause i simplified to what he got on that similar problem

 

[Doc Al]

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]

ohhh alright i got it, thank you very much