Find the velocity at the end of the race.

Question

The coefficient of friction between a race car’s wheels and the track is 1. The car starts from rest and accelerates at a constant rate for 200 m. Find the velocity at the end of the race.

Answer 1

Use the kinematic relation

 

v² - v₀² = 2ad

 

with

 

v₀ = 0

d = 200 meters

a = f/m = (μmg)/m = μg

μ = 1

 

v² = 2ad

 

v = √(2ad) = √[2(μg)(d)] = √[2(1)(9.8)(200)] m/s ≅ 62.61 m/s