Question

The average braking force of a 1000-kg car moving at 10 m/s braking to a stop in 5 s is

Answer 1

-2000 N

Step-by-step explanation:

First of all, let's calculate the acceleration of the car:

`a=(v-u)/(t)`

where

v = 0 is the final velocity of the car

u = 10 m/s is the initial velocity of the car

t = 5 s is the time elapsed

Substituting,

`a=(0-10 m/s)/(5 s)=-2 m/s^2`

where the negative sign means it is a deceleration.

Now we can calculate the average braking force:

`F=ma`

where m=1000 kg is the mass of the car. Substituting,

`F=(1000 kg)(-2 m/s^2)=-2000 N`

and the negative sign means the force is opposite to the direction of motion of the car.