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Question
A car moving with a uniform acceleration of 10 m/s2 on a straight road changes its speed from 10 m/s to 30 m/s. Find the time lapsed for the change of speed.
Solution
Acceleration of the car = 10 ms-2.
Initial velocity u = 10 m/s.
Final velocity v = 30 m/s.
We v = u + at.
T = (v- u)/a
T = (30 - 10 )/10 = 2 sec.
Time taken by car is 2 sec.
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