The reading of spring balance when a block is suspended from it in air, is $60\,N$. This reading is changed to $40\, N$ when the block is immersed in water. The specific density of the block is
$3$
$\frac{2}{3}$
$6$
$\frac{3}{2}$
The weight of a body in water is one third of its weight in air. The density of the body is ....... $g / cm ^3$
A body of density $\rho'$ is dropped from rest at a height $h$ into a lake of density $\rho$ , where $\rho > \rho '$ . Neglecting all dissipative forces, calculate the maximum depth to which the body sinks before returning to float on the surface.
A cube of ice floats partly in water and partly in kerosene oil. The radio of volume of ice immersed in water to that in kerosene oil (specific gravity of Kerosene oil $=0.8$, specific gravity of ice $=0.9$ )
Write the law of floatation and describe its cases.
An ice berg of density $900 Kg/m^3$ is floating in water of density $1000 Kg/m^3$. The percentage of volume of ice-cube outside the water is ...... $\%$