Determine at what angle j a disk suspended on an elastic thread will rotate if a second similar disk rotates underneath it at a distance h = 1 cm with an angular velocity w = 50 rad/s. The radius of the disks is R = 10 cm, the torsion modulus of the thread is f = 100 dynes•cm/rad, the air viscosity is assumed to be h = 1.8•10-4 dynes•s/cm2. Neglect edge effects. The air movement between the disks is considered laminar.

Answer. Format gif