Why is Static Friction Oriented Downwards on an Inclined Plane?

In summary, the problem involves a cord connecting a wall to a cylinder on an inclined plane. The cylinder has a mass of M and a radius of R and is at rest at t=0. The inclination angle is ϑ and the static and dynamic friction coefficients between cylinder and plane are μs and μd. The goal is to find the linear and angular acceleration of the cylinder. There is some confusion about the direction of static friction, but it is determined that the cylinder will roll down the slope and the direction of friction is opposite the motion. The direction of static friction can be determined by checking if it is enough to resist the motion.
  • #36
SammyS said:
Yes. You are correct.

With the forces in the directions indicated there is no way for the torque on the ball to be zero. It will have angular acceleration causing rotation in a counter-clockwise sense.

Ok...good. I about lost my marbles over that.
 
Physics news on Phys.org
  • #37
Kinta said:
Ok...good. I about lost my marbles over that.
Were they on an incline?
Which way were they rolling? :wink:

Anyway, save those marbles!
 

Similar threads

Back
Top