Question : A 210 𝑚 long train is moving due North at a speed of 25 𝑚/𝑠. A small bird is flying due South a little above the train with speed 5 𝑚/𝑠. The time taken by the bird to cross the train is
(A) 6𝑠
(B) 7𝑠
(C) 9𝑠
(D) 10𝑠
Answer : option (B)
Solution :
