Question

a car driver driving at a speed of 90km/h applies brakes and brings the car to rest in 20s the the acceleration of the car is​

Answer 1

Answer:

1.25 m/s²

Explanation:

Given:

Initial velocity (u) = 90 km/h = (90 * 5/18) m/s = -25 m/s

(Since the object is decelerating, we have taken the velocity as a negative value)

Final velocity (v) = 0 m/s

Time (t) = 20 seconds

To find:

Deceleration or negative acceleration (a)

Method to find:

v = u + at

⇒ 0 = -25+ 20a

⇒ 20a = 25

⇒ a = 25/20

⇒ a = 1.25 m/s²

Hence, the deceleration of the car is 1.25 m/s².