Question

A car is traveling at 20 m/s and a dog runs out in front
of it. The car has to come to an abrupt stop in 2
seconds or hit the dog. What is the car's acceleration?

Answer 1

Answer:

Below

Explanation:

To find the acceleration of the car you can use this formula and rearrange :

     vf = vi + at

We know that our time is 2 seconds, our initial velocity, vi, is 20 m/s, and our final velocity vf is 0 because the car comes to a stop before hitting the dog.

So we can just go ahead and plug in these values into the equation above :

     0m/s = 20m/s + (a)(2s)

     -20m/s = 2s(a)

Divide both sides by 2

     -10m/s^2 = a

Therefore the acceleration of the car is -10m/s^2 [forward]

     You could also write this as 10m/s^2 [back]

Hope this helps! Best of luck <3