A 280 N block rests on a 30° incline. (a) What is the normal force exerted by the incline on the

block? (b) What (static) friction force is needed to prevent the block from sliding down the
incline? (c) What is the minimum coefficient of static friction needed?

2 answers

a. mg*cosTheta
b. gravity forced down the plane=mg*sinTheta
c. mg*cosTheta*mu=mgSinTheta
mu=tanTheta
a. 242.5N
b. 140N
c. 0.5