A balloon of mass $m$ contains water of mass $M$ . If it is completely immersed in water, find the apparent mass of the balloon with water in it
$M + m$
$M -m$
$M$
$m$
A concrete sphere of radius $R$ has a cavity of radius $ r$ which is packed with sawdust. The specific gravities of concrete and sawdust are respectively $2.4$ and $0.3$ for this sphere to float with its entire volume submerged under water. Ratio of mass of concrete to mass of sawdust will be
A block of steel of size $ 5 cm × 5 cm × 5 cm $ is weighed in water. If the relative density of steel is $7,$ its apparent weight is
A silver ingot weighing $2.1 kg$ is held by a string so as to be completely immersed in a liquid of relative density $0.8$. The relative density of silver is $10.5$ . The tension in the string in $kg-wt$ is
Two cubical blocks identical in dimensions float in water in such a way that $1$ st block floats with half part immersed in water and second block floats with $3 / 4$ of its volume inside the water. The ratio of densities of blocks is ..........
A fluid container is containing a liquid of density $\rho $ is accelerating upward with acceleration a along the inclined place of inclination $\alpha$ as shown. Then the angle of inclination $ \theta $ of free surface is :