Question

A box that has a mass of 80 kg slides down a ramp with a 30 degree angle. The free-body diagram shows the forces acting on the box.

A block is shown on a 30-degree incline with a free body diagram drawn on the block with 2 force vectors. The first vector is pointing away from the surface of the incline and perpendicular to the surface, labeled F Subscript N Baseline. The second vector is pointing straight down to the center of the earth, labeled F Subscript g Baseline.

Ignoring friction and air resistance, what is the acceleration of the box, to the nearest tenth?

0.5 m/s2
4.9 m/s2
8.5 m/s2
9.8 m/s2

Answer 1

Resolve gravity into components parallel and perpendicular to the plane. The downhill component is mg sin(30°), so

a = (mg sin 30°) / m = g sin 30° = 9.8 × 0.5 = 4.9 m/s².

Answer: 4.9 m/s².