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Question
A body starts to slide over a horizontal surface with an initial velocity of 0.5 ms−1. Due to friction, its velocity decreases at the rate of 0.05 ms−2. How much time will it take for the body to stop?
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Solution
Initial velocity of body u = 0.5 ms−1.
Final velocity of the body v = 0 ms−1 as body comes to rest finally.
Retardation of body = 0.05 ms−2.
We know that v = u + at.
0 = 0.5 − 0.05t
T = 0.5/0.05
T = 10 sec.
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