Question

An 85 kg object is moving at a constant speed of 15 m/s in a circular path, which has a radius of 20 meters. What centripetal force is exerted on the body?

A. 42.50 N
B. 63.75 N
C. 956.25 N
D. 765.00 N

Answer 1

Centripetal force needed to move mass 'm' in a circle with radius 'r' at speed 'v' is

F = m · v² / r

F = (85 kg) ·(15 m/s)² / (20 m)

F = (85kg · 225m²) / (20 m·s²)

F = (85 · 225 / 20) (kg·m² / m·s²)

F = 956.25 kg·m/s²

F = 956.25 Newtons