Question

What is the magnitude of normal force acting on the block when it is resting on the flat surface? How does the normal force change as the angle of the ramp increases? Explain. (Assume that the ramps are frictionless surfaces.)

Answer 1

On the flat surface, the normal force is equal in magnitude to the weight of the block but acts in an opposite direction. From the information given,

weight of block = 52.7 N

1) When the block is at rest on a flat surface,

Normal force = weight

Thus,

Normal force = 57.2 N

2) As the angle of the ramp increases,

Normal force = Wcosθ

where

θ is the angle between the ramp and the ground.

If θ = 30,

Normal force = 57.2Cos30 = 49.5 N

If θ = 70,

Normal force = 57.2Cos70 = 19.6 N

Thus,

as the angle of the ramp increases, the normal force decreases