$A$ boat containing some iron pieces is floating in a pond. If the iron pieces are thrown into the water,the level of the water will:

Why do bubbles rise in a soda water bottle?

$A$ cylindrical block of area of cross-section $A$ and of material of density $\rho$ is placed in a liquid of density one-third of the density of the block. The block compresses a spring,and the compression in the spring is one-third of the length of the block. If the acceleration due to gravity is $g$,the spring constant of the spring is:

Assertion $(A)$: $A$ helium-filled balloon does not rise indefinitely in the air but halts after a certain height.
Reason $(R)$: Viscosity opposes the motion of the balloon. Choose any one of the following four responses:

$A$ $0.5\ kg$ mass of lead is submerged in a container filled to the brim with water and a block of wood floats on top. The lead mass is slowly lifted from the container by a thin wire and as it emerges into air the level of the water in the container drops a bit. The lead mass is now placed on the block of wood. As the lead is placed on the wood,what happens to the water level in the container?

$A$ rectangular block of mass $M$ and cross-sectional area $A$ floats on a liquid of density $\rho$. It is given a small vertical displacement from equilibrium; it starts oscillating with frequency $n$. Then: