- #1

Demetrius

## Homework Statement

Using the results from problem 2.18 for the setup shown in the Figure below show that if the system is to remain at rest, then the coefficient of friction:

a) between the stick and the ground must satisfy

$$

μ ≥ \frac {sin(Θ)cos(Θ)} {(1+cos(Θ))(2-cos(Θ))}

$$

## Homework Equations

The result from 2.18 is:

$$

F_f = \frac 1 2 ρgRcos(Θ)

$$

Which is the friction between the stick and the circle.

## The Attempt at a Solution

The sum of torques on the stick is (my origin is the point where the stick and circle is touching):

## \frac L 2 mgcos(Θ) + L F_fsin(Θ) = L Ncos(Θ) ##

This is how far I am.