Relative Motion in One Dimension - NEET Physics Questions
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Relative Motion in One Dimension

Question 11: moderate

A train of \(150\text{ metre}\) length is going towards north direction at a speed of \(10\text{ m/s}\). A parrot flies at the speed of \(5\text{ m/s}\) towards south direction parallel to the railways track. The time taken by the parrot to cross the train is:

(1988)

1. \(12\text{ sec}\)
2. \(8\text{ sec}\)
3. \(15\text{ sec}\)
4. \(10\text{ sec}\)
View Answer

Concept: Relative velocity for objects moving in opposite directions.
Length of train \(L = 150\text{ m}\)).
Speed of train \(v_T = 10\text{ m/s}\)). Speed of parrot \(v_P = 5\text{ m/s}\)).
Since they move in opposite directions, their relative speed is \(v_{rel} = v_T + v_P = 10 + 5 = 15\text{ m/s}\).
Time taken to cross: \(t = L/v_{rel} = 150/15 = 10\text{ s}\).