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A bird is flying towards south with a ve...

A bird is flying towards south with a velocity 40km/hr and a train is moving with a velocity 40km/hr towards east. What is the velocity of the bird w.r.t. an obserber in train:-

Text Solution

Verified by Experts

The correct Answer is:
`80 ms^(-1)`
Let t= time of accelerated motion of the helicopter.
Distance travelled by helicopter
+ Distanace travelled by sound
`rArr (1)/(2) xx 3 xx t^(2) =320 (30-t)rArr t=(80)/(3)sec`
Final velocity of helicopter
`v=u+at =0 +3 xx (80)/(3)= 80 m//s`.
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