Question

A car speeding 20 m/s sees a yellow light at the intersection 30 meters away and tries to come to a stop. They successfully come to a stop in 8 seconds, but were they able to

stop behind the line, or is their car in the intersection. In other words, how far do they
travel before coming to a complete stop? Is it less than or greater than 30 m?

Answer 1

Using the formula for stopping distance with uniform deceleration, it was calculated that the car traveled a total distance of 40 meters, which exceeds the 30 meters to the intersection, indicating the car stopped in the intersection.

Step-by-step explanation:

To determine if the car was able to stop behind the line before the intersection, we need to calculate the total stopping distance of the car. Given the car's initial speed of 20 m/s and a stopping time of 8 seconds, we can use the formula for uniform deceleration:

Stopping distance = (initial speed × time) / 2

In this case, the stopping distance = (20 m/s × 8 s) / 2 = 80 m / 2 = 40 m.

This calculated stopping distance is greater than the 30 meters away from the light, which means that the car will end up in the intersection before coming to a complete stop.