A train of length 200 m switches on its headlight when it starts movin

1.	A train of length 200 m switches on its headlight when it starts moving with acceleration 0.5 m/s2. Some time later, its tail light is switched on. An observer on the ground notices that the two events occur at the same place. The time interval between the two events is(a) 10√2s (b) 20 s (c) 20√2 s (d) 40 s
Answer» Correct Answer is: (c) 20√2 s The train has covered a distance of 200 m in the time interval. 200 m = 0 + 1/2 (0.5 m/s²)t². t = 20√2 s.

A train of length 200 m switches on its headlight when it starts moving with acceleration 0.5 m/s2. Some time later, its tail light is switched on. An observer on the ground notices that the two events occur at the same place. The time interval between the two events is(a) 10√2s (b) 20 s (c) 20√2 s (d) 40 s

Answer»

Correct Answer is: (c) 20√2 s

The train has covered a distance of 200 m in the time interval.

200 m = 0 + 1/2 (0.5 m/s²)t².

t = 20√2 s.

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