Consider a disk of mass `m`, radius `R` lying on a liquid layer of thickness T and coefficient of viscosity `eta` as shown in the fig.
A disc rotating with angularvelocity `omega` is placed on a viscous liquid of thickness T. Find the angle rotated by the disc before it comes to rest. (viscosity`=eta`, mass of disc `=M`, radius of disc `=R`)

Consider a disk of mass m , radius R lying on a liquid layer of thickness T and coefficient of viscosity eta as shown in the fig. The torque required to rotate the disk at a constant angular velocity Omega given the viscosity is uniformly eta .

Consider a disk of mass m , radius R lying on a liquid layer of thickness T and coefficient of viscosity eta as shown in the fig. The coefficient of viscosity varies as eta=eta_(0)x (x measured from centre of the disk) at the given instant the disk is floating towards right with a velocity v as shown, find the force required to move the disk slowly at the given instant.

Select ALL correct answer : A disc of radius R is placed over a horizontal table in such a way that plane of the disc is horizontal and rotated about its vertical axis passing through its center with angular velocity omega . A layer of grease of thickness l is present between the table and the disc.Coefficient of viscosity of grease is eta .Then, (A) torque needed to rotate the disc with constant angular velocity is (pi eta omega R^(4))/(4l) (B) torque needed to rotate the disc with constant angular velocity is (pi eta omega R^(4))/(2l) (C) power needed to rotate the disc with constant angular velocity is (pi eta omega^(2)R^(4))/(2l) (D) power needed to rotate the disc with constant angular velocity is (pi n omega^(2)R^(4))/(4l)

A disc has mass 'M' and radius 'R'. How much tangential force should be applied to the rim of the disc so as to rotate with angular velocity omega in time 't'?