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प्रश्न
A train starts from rest and moves with a constant acceleration of 2.0 m/s2 for half a minute. The brakes are then applied and the train comes to rest in one minute. Find the maximum speed attained by the train .
उत्तर
Initial velocity, u = 0
Acceleration, a = 2 m/s2
Let the final velocity be v before the brakes are applied.
Now,
t = 30 s
v = u + at
v = 0 + 2 × 30
⇒ v = 60 m/s
Maximum speed attained by the train, v = 60 m/s
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