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A table fan, rotating at a speed of 2400...

A table fan, rotating at a speed of 2400 rpm, is switched off and the resulting variation of the rpm with time is shown in the figure. The total number of revolutions of the fan before it comes to rest is

A

420

B

280

C

190

D

16800

Text Solution

Verified by Experts

The correct Answer is:
B
The corresponding (Rev/sec) graph is (Rev/sec)

Area under this curve gives the total number revolutions
`Delta = (1)/(2) (8)(30)+(10 xx8)+(16)(10)`
= 280 revolutions
D is only correct option
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