A Block of Mass M Is at Rest on an Inclined

Multiple Choice

A block of mass m is at rest on an inclined plane that makes an angle of 30 ^o with the horizontal. Which of the following statements about the force of static friction is true?

A) f_s > mg
B) f_s > mg cos 30^o
C) fs = mg cos 30^o
D) f_s = mg sin 30^o
E) None of these statements is true.