Question

A 1500 kg vehicle is moving on a dry pavement where the coefficient of friction is 0.80. If the vehicle is traveling at 25 m/s, what minimum distance is required to stop it when the brakes are applied. a. 40 m
b. 55 m
c. 72 m
d. 64 m

Answer 1

Answer:

The minimum distance is 40 m.

(a) is correct option.

Explanation:

Given that,

Mass of vehicle = 1500 kg

Coefficient friction = 0.80

Speed = 25 m/s

We need to calculate the acceleration

Using frictional force

$f=\mu mg$

Put the value into the formula

$ma=\mu mg$

$a = \mu g$

We need to calculate the distance

Using equation of motion

$v^2=u^2+2as$

Put the value into the formula

$0=25^2-2times\mu g\times s$

$s=\dfrac{25^2}{2\times0.80\times9.8}$

$s=39.8 = 40 m$

Hence, The minimum distance is 40 m.