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Question
A vehicle is accelerating on a straight road. Its velocity at any instant is 30 km/h. After 2 s, it is 33.6 km/h, and after further 2 s, it is 37.2 km/h. Find the acceleration of the vehicle in m s-2. Is the acceleration uniform?
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Solution
Acceleration = Change in velocity/time taken
In the first two seconds,
Acceleration = [(33.6 - 30)/2] km/s2
= 1.8 km/s2
= 0.5 m/s2 …(i)
In the next two seconds,
Acceleration = [(37.2 - 33.6)/2] km/s2
= 1.8 km/s2
= 0.5 m/s-2…(ii)
From (i) and (ii), we can say that the acceleration is uniform.
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