A car slows down from 21 m/s to rest in a distance of 63m. Assuming the car has a constant acceleration, calculate the time it took to come to a stop.

-3.5 m/s²

Explanation:

Initial Velocity = 21m /sFinal velocity = 0m/s Distance = 63 m .Acclⁿ = ?

We know that :-

Stopping distance = u²/2(-a)

63m = (21m/s)² / -2a

a = - 21 * 21 / 63 * 2 m/s²

a = - 3.5 m/s²

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