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A ceiling fan rotates about its own axi...

A ceiling fan rotates about its own axis with some angular velocity. When the fan is switched off, the angular velocity becomes `(1/4)`th of the original in time 't' and 'n' revolutions are made in that time. The number f revolutions made by the fan during the time interval between switch of and rest are (Angular retardation is uniform)

Text Solution

Verified by Experts

The correct Answer is:
C
`((omega)/(4))^(2)=omega^(2)-2alphan(2pi)`
`therefore 2alphan(2pi)=omega^(2)-(omega^(2))/(16)`
`therefore 2pin=(15)/(16)((omega^(2))/(2alpha))`
`0=omega^(2)-2alphan'`
`therefore 2pin'=(omega^(2))/(2alpha)" "therefore n'=(16)/(15)n`
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