College

A car company is performing brake tests on one of its cars. The car reaches a speed of 160 km/h and then hits the brakes to slow down at a rate of [tex]11.0 \, \text{m/s}^2[/tex].

(a) How long does it take the car to stop?

(b) How far does the car travel when braking?

Answer :

Final answer:

The car takes 4.04 seconds to come to a stop from a speed of 160 km/h and travels a distance of 89.78 meters during breaking.

Explanation:

To determine how long it takes for the car to stop and the distance it travels during braking, we can use the kinematic equations of motion. First, we need to convert the speed of the car from km/h to m/s by multiplying it by ⅕. With a speed of 160 km/h, which is approximately 44.44 m/s, and a deceleration rate of 11.0 m/s2, we can calculate the time taken to stop using the equation time = velocity ÷ deceleration.

(a) The time taken to stop is:

time = 44.44 m/s ÷ 11.0 m/s2 = 4.04 s

(b) To calculate the distance traveled when braking, use the equation distance = 0.5 × (initial velocity + final velocity) × time. The final velocity is zero since the car comes to a stop.

distance = 0.5 × (44.44 m/s + 0) × 4.04 s = 89.78 m

Hence, the car takes approximately 4.04 seconds to stop and travels around 89.78 meters while braking.