A train of \(150 \mathrm{~m}\) length is going towards north direction at a speed of \(10…
A train of \(150 \mathrm{~m}\) length is going towards north direction at a speed of \(10 \mathrm{~ms}^{-1}\). A parrot flies at the speed of \(5 \mathrm{~ms}^{-1}\) towards south direction parallel to the railway track. The time for which the parrot flies alongside the train is
\(12 \mathrm{~s}\)
\(30 \mathrm{~s}\)
\(10 \mathrm{~s}\)
\(5 \mathrm{~s}\)
Solution
According to question,
Relative velocity of parrot with respect to the train,
\(\begin{aligned}
v_{p t} & =v_t-v_p \\
& =10-(-5) \\
& =10+5=15 \mathrm{~m} / \mathrm{s}
\end{aligned}\)
\(\therefore\) Time taken by the parrot to fly along side the train is given as
\(t=\frac{\text { length } \text { of train }}{v_{p t}}=\frac{150}{15}=10 \mathrm{~s}\)