The ratio of masses of a cubical block of wood and a chunk of concrete is $\frac{3}{5}$ so that the combination just floats with its entire volume submerged under water. If the specific gravity of wood is $0.5$,then the specific gravity of concrete will be:

$A$ jar is filled with two non-mixing liquids $1$ and $2$ having densities $\rho_1$ and $\rho_2$ respectively. $A$ solid ball,made of a material of density $\rho_3$,is dropped in the jar. It comes to equilibrium in the position shown in the figure. Which of the following is true for $\rho_1, \rho_2$ and $\rho_3$?

The weight of an empty balloon on a spring balance is $w_1$. The weight becomes $w_2$ when the balloon is filled with air. Let the weight of the air itself be $w$. Neglect the thickness of the balloon when it is filled with air. Also,neglect the difference in the densities of air inside and outside the balloon. Then:

An empty glass jar is submerged in a tank of water with the open mouth of the jar downwards, so that the air inside the jar is trapped and cannot escape. As the jar is pushed down slowly, the magnitude of the net buoyant force on the system of the volume of gas trapped in the jar and the jar:

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

$A$ wax candle floats vertically in a liquid of density twice that of wax. The candle burns at the rate of $4\ cm/hr$. Then, with respect to the surface of the liquid, the upper end of the candle will: