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A bird of mass 1.23 kg is able to hover ...

A bird of mass 1.23 kg is able to hover by imparting a downward velocity of `10 m//s` uniformly to air of density `rho kg//m^(3)` over an effective area `0.1m^(2)` the acceleration due to gravity is `10m//s^(2)` then the magnitude of `rho` in `kg//m^(3)`

A

0.34

B

0.89

C

1.23

D

4.8

Text Solution

Verified by Experts

The correct Answer is:
C
`"Weight of bird"="force exerted by the bird by moving its wings. "rho Au^(2)=mg" "(F=Au^(2)rho)`
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