Question

A bird is flying due North at a speed of 10 m/s. A
train 250 m long is also travelling due North at a
speed of 20 m/s. Bird and train are moving in the
same vertical plane. How long will the train take to
overtake the bird completely?​

Answer 1

Answer:

25 seconds

It is given the velocity of bird with respect to ground is 10 m/s while the velocity of train with respect to ground is 20 m/s then the relative velocity will 20-10 = 10 m/s

Thus time=distance/speed

hence time=250/10=25 s

Answer 2

Answer:

since the bird and the train are travelling in same vertical plane, the relative speed of with respect to will be (20 - 10 =) 10m/s.

time taken by train to cross the bird will be 250/10 = 25 seconds.

hope it may help u.