Write Archimedes’ principle.

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 wooden block, with a coin placed on its top, floats in water as shown in fig. the distance $l $ and $h$ are shown there. After some time the coin falls into the water. Then

A metal ball of density $7800\  kg/m^3$ is suspected to have a large number of cavities . It weighs $9.8$ $kg$ when weighed directly on a balance and $1.5$ $kg$ less when immersed in water . The fraction by volume of the cavities in the metal ball is approximately ....... $\%$

A cubical block of density $\rho $ is floating on the surface of water. Out of its height $\mathrm{L}$, fraction $\mathrm{x}$ is submerged in water. The vessel is in an elevator accelerating upward with acceleration $\mathrm{a}$. What is the fraction immersed ?

A metallic block of density $5\,gm \,cm^{-3}$ and having dimensions $5 cm × 5 cm × 5 cm$ is weighed in water. Its apparent weight will be