An ornament weighs $10\, g$ in air and $6\, g$ in water. The density of the material of the ornament is $20\, g/cc$. The volume of the cavity in the ornament is ........ $cc$.

$A$ block of wood of volume $V$ floats in water with half of its volume submerged. The same block floats in an oil with $0.8 \,V$ volume submerged. If the density of water is $1000 \,kg \,m^{-3}$, then the density of the oil is

When does a body sink in a liquid? Explain.

$A$ block of wood is floating on water at $0^{\circ} C$ with volume $V_0$ above water. When the temperature of water increases from $0^{\circ} C$ to $10^{\circ} C$,the change in the volume of the block that is above water is best described schematically by which graph?

$A$ solid floats such that its $(1/3)$rd part is above the water surface. Then,the density of the solid is

$A$ hollow sphere of mass $M$ and radius $R$ is immersed in a tank of water (density $\rho_w$). The sphere would float if it were set free. The sphere is tied to the bottom of the tank by two wires which make an angle of $45^{\circ}$ with the horizontal as shown in the figure. The tension $T_1$ in each wire is: