A rubber ball of mass m and radius r is submerged in water to a depth h and released. What height will the ball jump up to above the surface of the water? Neglect ther resistance of water and air. Take water density `rho`.

Explanation

Let the ball go up by x above the level of water.Let us now consider energy conservation between the initial and final positions. In both the positions kinetic energy of the body is zero. The potential energy in the first position with reference to the water level is – mgh plus the work done by an external agent against the buoyant force which is `((4)/(3)pir^(3)rho g)h`, where `rho` is the density of the water

or `" "–mgh + ((4)/(3)pi r^(3) rho g)h=mgx rArr`
`x=((4//3)pi r^(3) rho-m))/(m)xxh`