A train is travelling at a speed of 90 km h-1. Brakes are applied so as to produce a uniform acceleration of, -0.5 m s-2. Find how far the train will go before it is brought to rest.
Initial speed, u = 90 km/h2
= 
= 25 m/s
Final speed, v = 0 (As the train stops)
Acceleration, a = -0.5 m/s2
And,
Distance travelled, s =?
Now, v2 = u2 + 2as
(0)2 = (25)2 + 2 × (-0.5) × s
0 = 625 – 1 × s
s = 625 m
Therefore, 625 metres is the distance travelled by the train before it is brought to rest.
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