Final answer:
The stopping distance of a car is the sum of its reaction distance (distance covered during the driver's reaction time) and its braking distance (distance covered from the time brakes are applied until the car stops).
Step-by-step explanation:
The stopping distance of a car is equal to the sum of its reaction distance and braking distance. The reaction distance is the distance the car travels during the driver's reaction time before the brakes are applied. It's calculated by considering that the car maintains a constant velocity during this reaction time.
The braking distance is the distance the car travels from the time the brakes are applied until the car comes to a stop. Therefore, the correct answer is C. the sum of its reaction distance and braking distance.
During a reaction time of 0.500 seconds and an initial speed of 30.0 m/s, the car covers a distance (reaction distance) which is calculated as speed multiplied by reaction time. Assuming no acceleration during reaction time (areaction = 0), this distance would be 30.0 m/s multiplied by 0.500s, resulting in 15.0 meters.
To find the total stopping distance, this reaction distance is added to the braking distance, which can vary based on road conditions such as dry or wet pavement.