High School

A driver in a car, originally moving at 6.6 m/s, applies the brakes until the car comes to a stop. The car moves a distance of 6.4 m while braking.

How much time in seconds did it take for the car to stop?

Assume constant acceleration during braking.

Answer :

Final answer:

The car took approximately 3.41 seconds to come to a stop.

Explanation:

The distance the car travels while braking is 6.4m. To find the time it took for the car to stop, we can use the equation v^2 = u^2 + 2as, where v is the final velocity (0 m/s) and u is the initial velocity (6.6 m/s). Rearranging the equation, we have t = (v - u) / a, where a is the acceleration. Since the car is coming to a stop and the acceleration is constant, we can use the formula a = -u^2 / (2s). Plugging in the values, we get t = -6.6^2 / (2 * -6.4), which gives us t ≈ 3.41 seconds.