Question

How does an increase in speed affect the reaction distance and the braking distance?

a) An increase in speed increases both the reaction distance and the braking distance.
b) An increase in speed decreases both the reaction distance and the braking distance.
c) An increase in speed increases reaction distance but does not affect braking distance.
d) An increase in speed increases braking distance but does not affect reaction distance.

Answer 1

(A) An increase in speed results in increases in both reaction distance and braking distance because the vehicle covers more ground during the driver's reaction time and requires more distance to stop due to higher kinetic energy.

Step-by-step explanation:

An increase in the speed of a vehicle affects its reaction distance and braking distance in two distinct ways. When a driver detects a need to stop, the reaction distance is the distance the car travels during the driver's reaction time, which is generally constant. However, as speed increases, the distance covered in that fixed reaction time also increases. On the other hand, the braking distance is the distance a car travels once the brakes are applied until it comes to a complete stop. This distance increases not linearly, but exponentially with speed, due to the kinetic energy being proportional to the square of the speed. Given these considerations, the correct statement is: (a) An increase in speed increases both the reaction distance and the braking distance.