A car moving with speed 20 m/s applies brakes and stops in 5 s. The distance covered during braking is MCQ with Answer and Explanation

A car moving with speed 20 m/s applies brakes and stops in 5 s. The distance covered during braking is

A. 200 m

B. 100 m

C. 25 m

D. 50 m

Answer: Option D

Solution (By JKExamLibrary)

u=20, v=0, t=5, a = (0-20)/5 = -4 m/s². s = ut + ½at² = 20×5 + ½×(-4)×25 = 100 - 50 = 50 m. Or average velocity = (20+0)/2 = 10 m/s, distance = 10×5 = 50 m.

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