Suppose you are in a moving car and the motor stops running. You step on the brakes and slow the car to half speed. If you release your foot from the brakes, will the car speed up a bit, or will it continue at half speed and slow due to friction?

See the answer below

Explanation:

If you step on the brake of a car while driving, the frictional force between the tires of the car and the surface of the road increases in opposition to the motion of the car. Consequently, the car slows down.

If you release your foot from the brake pedal when the car is still at half speed, the frictional force reduces and the car speeds up a bit even without pressing the throttle. Eventually, the frictional force will slow down and stop the car if the throttle is not pressed.

d) physical means can be used to separate the components of air.