A flat disc of radius 'R' lie son the horizontal surface. The pressure between the disc and the surface decreases linearly with distance from the centre r due to its weight per unit area from 2P_(0) at th ecentre to P_(0) at r = R at the circumference. The coefficient of friction between the disc and the surface is 'mu'. Find the power delivered by the external agent to rotate the disc with a constant angular velocity omega

A flat disc of radius 'R' lie son the horizontal surface. The pressure

1.	A flat disc of radius 'R' lie son the horizontal surface. The pressure between the disc and the surface decreases linearly with distance from the centre r due to its weight per unit area from 2P_(0) at th ecentre to P_(0) at r = R at the circumference. The coefficient of friction between the disc and the surface is 'mu'. Find the power delivered by the external agent to rotate the disc with a constant angular velocity omega
Answer» `( 5)/( 6) pi P_(0) R^(3) omega MU` `( 7)/( 6) pi P_(0 ) R^(3) omega mu` `(3)/( 6) pi P_(0) R^(3) omega mu` `(11)/( 6) pi P_(0)R^(3) omega mu` Answer :A

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