Question

A driver traveling at a speed of 21 m/s tops a hill and spots a deer standing in the middle of the road 90 meters away. He hits the brakes and panic stops the car in 8 seconds. How far did the car travel before stopping?

Answer 1

Answer:

84m

Explanation:

Using the kinematics equation we can come up with the answer:

$d=\dfrac{Vf+Vi}{2}\times t$

Where:

Vf = final velocity

Vi = initial velocity

t = time

In your problem we have the following given:

Vf= 0 m/s

Vi = 21 m/s

t = 8 seconds

The Vf is zero because the car stopped. The distance given in this case is not useful in determining the car's distance so we will solve it. So just fill in the equation with the given:

$d=\dfrac{Vf+Vi}{2}\times t\\\\d=\dfrac{0m/s+21m/s}{2}\times 8s\\\\d=10.5m/s\times 8s=84m$

Thankfully, the deer was not hit!