posted by Diana .
A block with a mass 4.0 kg is held in equilibrium on an incline of angle θ = 42° by a horizontal force F.
a)Find the magnitude of the normal force.
b) Find the magnitude of F. (Ignore friction.)
a) The applied horizontal force is balanced by the weight and the normal force applied to the block by the incline.
Let the normal force be Fn.
Fn = M g cos42 + F sin42
F cos42 = M g sin42
Solve for Fn
Fn = M g (cos42 + sin42*tan42) = 52.7 N
W = 39.2 N
b) F = 35.3 N