The faster you’re traveling, the __________ you will need to stop.

The faster you’re traveling, the __________ you will need to stop.

• A. The same amount of friction
• B. Less friction
• C. No friction
• D. More friction

Answer: (C)

Stopping relies on the braking force provided by friction between the tires and the road. To bring a car to rest from a higher speed in the same amount of time or over the same distance, you must generate a larger deceleration. Since braking force comes from friction, you need more friction to produce that larger force. If friction isn’t increased, you won’t slow down as quickly, or you may not be able to stop at all if the available friction is insufficient. So, as speed increases, you will need more friction to stop effectively.

Stopping relies on the braking force provided by friction between the tires and the road. To bring a car to rest from a higher speed in the same amount of time or over the same distance, you must generate a larger deceleration. Since braking force comes from friction, you need more friction to produce that larger force. If friction isn’t increased, you won’t slow down as quickly, or you may not be able to stop at all if the available friction is insufficient. So, as speed increases, you will need more friction to stop effectively.