A crate slides down a ramp at angle 48 degree to horizontal. The coefficient of limiting friction is 0.48. Find the options for the acceleration of the crate down the ramp.

Answer 1

The maximum friction force opposing motion down the ramp, with a static friction coefficient of 0.48, is M g 0.48 cos 48 = 0.32 M g. That is less than the downward component of gravity, M g sin 48 = 0.74 M g
Therefore sliding will begin, and the speed will accelerate.