Question

A 745 kg race car experiences an applied force from the engine of 38900 N and a frictional force of 34000 N. How long does it take to go from rest to 21 m/s ?

Answer 1

0.215seconds

Step-by-step explanation:

m = 745kg, Fe = 38900N, Fr = 34000, v = 21m/s, t = ?

Netforce{Fn} = Fe + Fr

Fn = 38900 + 34000

Fn = 72900N

Fn = mv/t

Making time subject of the formula

We have;

t = mv/Fn

t = (745 × 21)/72900

t = 0.215s