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As mosquito is sitting on an L.P. record...

As mosquito is sitting on an L.P. record disc rotating on a trun tabel at `33 1/3` revolutions per minute. The distance of the mosquito from the centre of the turn table is 10 cm. Show that the friction coefficient between the record and the mosquito is greater than `pi^2/81`. Take `g=10m/s^2`

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The correct Answer is:
A

A mosquito is sitting on an L.P record disc and rotating on a turn table at `33 1/2` rpm.
`n=33/1/3 rpm`
`100(3xx60)rps`
`:. omega==2pixx100/180`
`=(10pi)/9 rad/sec`
`r=10cm=0.4m`
`g=10 m/sec^2`
`mumg?=mromega^2`
`:. mugt(romega^2)/g.=(0.1xx(10pi/9)^2)/10`
`rarr mugt(pi^2/81)`
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