A large ship can float but a steel needle sinks because of
Viscosity
Surface tension
Density
None of these
A wooden cylinder floats vertically in water with half of its length immersed. The density of wood is
Mumbai needs $1.4 \times 10^{12} L$ of water annually. Its effective surface area is $600 \,km ^2$ and it receives an average rainfall of $2.4 \,m$ annually. If $10 \%$ of this rain water is conserved, it will meet approximately
A hollow sphere of mass $M$ and radius $r$ is immersed in a tank of water (density $\rho$$_w$ ). The sphere would float if it were set free. The sphere is tied to the bottom of the tank by two wires which makes angle $45^o$ with the horizontal as shown in the figure. The tension $T_1$ in the wire is :
The fraction of a floating object of volume ${V_0}$ and density ${d_0}$ above the surface of a liquid of density $d$ will be
A fire hydrant delivers water of density $\rho $ at a volume rate $L$. The water travels vertically upward through the hydrant and then does $90^o$ turn to emerge horizontally at speed $V$. The pipe and nozzle have uniform cross-section throughout. The force exerted by the water on the corner of the hydrant is