A beaker is filled in with water is accelerated $a $ $m/s^2$  in $+x$ direction. The surface of water shall make on angle

A vessel containing water is given a constant acceleration a towards the right, along a straight horizontal path. Which of the following diagram represents the surface of the liquid

A rectangular block is $10 \,cm \times 10 \,cm \times 15 \,cm$ in size is floating in water with $10 \,cm$ side vertical. If it floats with $15 \,cm$ side vertical, then the level of water will ……….

A large ship can float but a steel needle sinks because of

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 ……. $\%$