a ceiling fan rotating at its full speed of 1200rpm is swithched off at t =0 .it cums at rest at t=5 s assuming uniform motion ,the no. of revolution made by it b4 cuming to rest ??
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Expert's answer
2012-12-10T12:00:06-0500
Equation of motion is f = wt-et^2/2 where f is number of revolutions, t is time, w is initialrotation speed and e is angular deceleration. it is obvious that e = w/(1/12 of minute) = 14400minute^(-2)
Hence f = 1200t-14400t^2/2, t=1/12 of minute = 5 sec. f = 100-50 = 50 revolutions will be done.
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