Question

A car is moving with a velocity 20 m s -1 . The brakes are applied to retard it at a rate of 2 ms-2. What will be the velocity after 5 s of applying the brakes ?

February 16, 2024

Answer

Acceleration (a) = – 2 m s^-2

time (t) = 5 s

Initial Velocity (u) = 20 m s ^-1

– 2 = $v-20\over 5$

or, v – 20 = – 2 × 5

or, v = – 2 × 5 + 20 = 10 ms ^-1

Hence, final velocity = 10 m s ^-1.

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