Frictional forces question (1 Viewer)

[astroman]

A 5.0-kg crate is resting on a horizontal plank. The coefficient of static friction is 0.60 and the coefficient of kinetic friction is 0.50. After one end of the plank is raised so the plank makes an angle of 35° with the horizontal, the force of friction is ?

 

[astroman]

bump

 

[Silly Sausage]

Draw a FBD with the xy intercept tilted and you should find three forces acting upon it.

Sum the forces in the x-direction: =0
and the y-direction:

Solve for static friction in the x-direction