A spherical ball of the radius R is made by joining two hemispherical parts. The two parts have density `rho` and `2rho`. When placed in a water tank, the ball floats while remaining completely submered.
(a) If density of water is `rho_(0)`, find `rho`
(b) Find the time period of small angular oscillations of the ball about its equilibrium position. Neglect viscous forces.

Answer

(a) `rho=(2rho_(0))/(3)` (b) `T=2pisqrt((123)/(40g))`