Question

A train of $150\, m$ length is going towards north direction at a speed of $10 \,ms ^{-1}$. A parrot flies at a speed of $5 \,ms ^{-1}$ towards south direction . parallel to the railway track. The time taken by the parrot to cross the train is equal to

• A. 12 s
• B. 8 s
• C. 15 s
• D. 10 s

Answer 1

Answer: (D)

10 s

Answer 2

Relative velocity of the parrot w.r.t. the train $=[10-(-5)] \,m / s =15\, m / s$ Time taken by the parrot to cross the train $=\frac{150}{15}=10\, s$