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A bird is sitting on the top of a vertic...

A bird is sitting on the top of a vertical pole 20 m high and its elevation fron a point O on the ground is `45^@`,It Files off horizontally straight away from the point O.After one second , the elevation of the bird fron O is reduced to `30^@` Then the speed (in m/s) of the bird is

A

`40(sqrt(3)-sqrt(2))`

B

`20sqrt(2)`

C

`20(sqrt(3)-1)`

D

`40(sqrt(2)-1)`

Text Solution

Verified by Experts

The correct Answer is:
C
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