Question

your friend’s car has died and needs to be pushed off the road. the car is sitting on a smooth road, and after it is moving you will push it on to a smooth paved shoulder. which of the following statements is true about the forces involved in moving the car?

(1 point)

it requires an equal amount of force to start the stopped car moving on a smooth and to keep the car moving on a smooth surface.

it requires more force to start a stopped car moving on smooth surface than to keep the car moving onto a smooth surface of the shoulder.

it requires less force to start a stopped car moving on smooth surface than to keep the car moving onto a smooth surface of the shoulder.

Explanation:

To determine the correct statement, we analyze the forces involved. Static friction (force needed to start a stationary object moving) is generally greater than kinetic friction (force needed to keep an object moving at a constant velocity) for the same surfaces. Here, the car is on smooth surfaces, but starting it (overcoming static friction) requires more force than keeping it moving (overcoming kinetic friction).

• The first option is incorrect because static and kinetic friction (even on smooth surfaces) aren't equal.
• The second option is correct: Starting the stopped car (static friction) needs more force than keeping it moving (kinetic friction) on smooth surfaces.
• The third option is incorrect as it contradicts the relationship between static and kinetic friction.

Answer:

It requires more force to start a stopped car moving on smooth surface than to keep the car moving onto a smooth surface of the shoulder.