A car travelling at 30 mph takes 10 m to come to a complete stop. Consider the work done by the brakes when stopping to estimate the distance required to bring the car to a complete stop from 75 mph. What is this distance

Respuesta :

Answer:

The value of the distance S = 62.5 m

Explanation:

From third law of motion

[tex]v^{2} = u^{2} + 2 as\\[/tex]

v = 0 & u = 30

So 0 = [tex]30^{2}[/tex] + 2 × a × 10

a = - 45 [tex]\frac{m}{s^{2} }[/tex]

When the car speed is 75 [tex]\frac{mi}{hr}[/tex]  then in that case

u =  75 [tex]\frac{mi}{hr}[/tex] , v = 0

[tex]v^{2} = u^{2} + 2 as\\[/tex]

[tex]75^{2} = - 2 a S[/tex]

[tex]S = \frac{75^{2} }{-2 (-45)}[/tex]

S = 62.5 m

This is the value of the distance.