A worker stands still on a roof sloped at an angle of 43° above the horizontal. He is prevented from slipping by a static frictional force of 520 N. Find the mass of the worker.

Question

A worker stands still on a roof sloped at an angle of 43° above the horizontal. He is prevented from slipping by a static frictional force of 520 N. Find the mass of the worker.

Damon · Answer

I guess he is JUST prevented from slipping normal force = m g cos 43 force down slope = m g sin 43 so m g sin 43 = 520