Question

A car’s brakes decelerate it at a rate of -1.70 m/s2. What is the time, in seconds, required to slow the car from 15 m/s to 9.0 m/s?

Answer 1

Answer:

t = 3.52 s

Explanation:

Given that,

The deceleration of a car is, a = -1.7 m/s²

The initial velocity of the car, u = 15 m/s

Final velocity of the car, v = 9 m/s

We need to find the time that is required to slow the car from 15 m/s to 9 m/s. The definition of acceleration is :

$a=\dfrac{v-u}{t}\\\\t=\dfrac{v-u}{a}\\\\t=\dfrac{9-15}{-1.7}\\\\t=3.52\ s$

So, it will take 3.52 seconds to slow the car from 15 m/s to 9 m/s.