Equilibrium friction on an incline

AI Thread Summary
The discussion focuses on determining the angle at which the greatest coefficient of friction is required for a uniform pole resting on an incline, secured by a horizontal rope. Participants emphasize the importance of analyzing the forces and torque acting on the pole, specifically the static friction force and its relationship to the incline's angle. The equations for the sum of forces and torques must be set to zero, incorporating the normal components of tension and weight. A suggestion is made to resolve the tension in terms of mass and gravitational force relative to the angle. Understanding these dynamics is crucial for solving the problem effectively.
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Homework Statement


A uniform pole of mass is at rest on an incline of angle , secured by a horizontal rope as shown in the figure.
http://session.masteringphysics.com/problemAsset/1034182/4/RW-12-57.jpg
For what angle does the situation require the greatest coefficient of friction?

Homework Equations



Sum of all forces, x and y, as well as torque equaling to zero.

The Attempt at a Solution



I got that the friction force would be static acting upward on the ramp, being Fs=musmgsin. and the angle would be the same as the theta in the picture. any ideas on how to start?
 
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bakin said:

Homework Statement


A uniform pole of mass is at rest on an incline of angle , secured by a horizontal rope as shown in the figure.
http://session.masteringphysics.com/problemAsset/1034182/4/RW-12-57.jpg
For what angle does the situation require the greatest coefficient of friction?

Homework Equations



Sum of all forces, x and y, as well as torque equaling to zero.

The Attempt at a Solution



I got that the friction force would be static acting upward on the ramp, being Fs=musmgsin. and the angle would be the same as the theta in the picture. any ideas on how to start?

Actually you have a good start already.

Write out the equations for the Σ F and Σ T to be 0, being sure to include the Normal component of Tension with the normal component of the weight to the incline. (The presumption is that the rope must be horizontal for any θ.)

The Σ T should allow you to resolve the Tension in terms of mg and θ.
 
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