A coin kept at a distance of 5 cm from the centre of a turntable of radius `1.5 m` just begins to slip when the turntable rotates at a speed of `90`r.p.m. Calculate the coefficient of static friction between the coin and the turntable `[g = 9.8 m//s^(2)]`

Explanation

Given that, distance at which coin is kept `(r ) = 5` cm
`= 0.05m`, radius of turn table `(R ) = 1.5 Hz`
Limiting force of static friction = Centripital force
`mu_(s)mg = mromega^(2)`
`:. mu_(s) = (romega^(2))/(g) = (r(2pin)^(2))/(g)`
`:. mu_(s) = (4rpi^(2)n^(2))/(g)`
`= (4xx 0.05 xx (3.14)^(2) xx (1.5)^(2))/(9.8)`
`:. mu_(s) = 0.4527`