Question

A 1000 kg car crashed into a barrier. The car changed speed from 30 m/s to 20 m/s in 0.2 seconds. What force did the barrier apply to stop the car?

Answer 1

Answer: -50000

Step-by-step explanation:

Answer 2

Force = -50000 Newton

Step-by-step explanation:

Given the following data;

Initial velocity, u = 30 m/s

Final velocity, v = 20 m/s

Time = 0.2secs

Mass = 1000 kg

First of all, we have to solve for its acceleration.

Acceleration = (v - u)/t

Substituting into the equation, we have

Acceleration = 20 - 30)/0.2

Acceleration = -10/0.2

Acceleration = -50m/s²

To find the force;

Force = mass * acceleration

Force = 1000 * (-50)

Force = -50000 Newton. The value of the force is negative because it stopped the motion of the car.

Therefore, the barrier applied a force of -5,0000 Newtons to stop the car.