Question

A student drives her car at 54.0 km/h along a level (horizontal) curve. The combined mass of the car is 1250 kg. If the

curve has a radius of 70.0 m, what centripetal force must be supplied by friction to keep the car from skidding?

Answer 1

4020 N

Step-by-step explanation:

First convert km/h to m/s.

54.0 km/h × (1000 m / km) × (1 h / 3600 s) = 15.0 m/s

Sum of the forces in the radial direction:

∑F = ma

F = m v² / r

F = (1250 kg) (15.0 m/s)² / 70.0 m

F ≈ 4020 N