An electric fan, with effective area of ...

An electric fan, with effective area of cross-section 'A', accelerates air of density 'rho' to a speed 'v'. What is the power needed for this process ?

`rho Av`

`.^(1)//_(2) rho Av`

`rho Av^(2)`

`.^(1)//_(2) rho Av^(3)`

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Verified by Experts

The correct Answer is:

`P = (1)/(2) A upsilon^(3) rho`.

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