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

A bird of mass 1.23 kg is able to haver 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 excted by the bird by moving its wings `rhoAu^(2)=mg (F=Au^(2)rho)`
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