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The blades of a windmill sweep out a cir...

The blades of a windmill sweep out a circle of area A. If the wind flows at a velocity v perpendicular to the circle, then the mass of the air of density `rho` passing through it in time t is

A

`Avrhot`

B

`2Avrhot`

C

`Av^2rhot`

D

`1/2Avrhot`

Text Solution

Verified by Experts

The correct Answer is:
A
Volume of wind flowing per second = Av
Mass of wind flowing per second = `Avrho`
Mass of air passing in time t s = `Avrhot`
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