$A$ cube made of a material having a density of $0.9 \times 10^3 \ kg/m^3$ floats between water (density $1.0 \times 10^3 \ kg/m^3$) and a liquid of density $0.7 \times 10^3 \ kg/m^3$. What part of the cube is immersed in water?

An aluminium sphere is dipped into water. Which of the following is true?

Two rods of the same material and length have their electric resistance in the ratio $1:2$. When both rods are dipped in water,the correct statement will be:

$A$ body floats in water with $40 \%$ of its volume outside water. When the same body floats in an oil, $60 \%$ of its volume remains outside oil. The relative density of oil is

$A$ cubical block of wood of specific gravity $0.5$ and a chunk of concrete of specific gravity $2.5$ are fastened together. The ratio of the mass of wood to the mass of concrete which makes the combination to float with its entire volume submerged under water is

$A$ hollow sphere of external radius $R$ and thickness $t$ $(t \ll R)$ is made of a metal of density $\rho$. The sphere will float in water if: