If the terminal speed of a sphere of gold (density $= 19.5\, kg/m^3$) is $0.2\, m/s$ in a viscous liquid (density $= 1.5\, kg/m^3$), find the terminal speed of a sphere of silver (density $= 10.5\, kg/m^3$) of the same size in the same liquid....... $m/s$

A solid cylinder of mass $m$ and volume $v$ is suspended from ceiling by a spring of spring constant $k$ . It has cross-section area $A$ . It is submerged in a liquid of density $\rho $ upto half its length. If a small block of mass $M_o$ is kept at the centre of the top, the amplitude of small oscillation will be 

The height of water in a tank is $H$. The range of the liquid emerging out from a hole in the wall of the tank at a depth $\frac {3H}{4}$ form the upper surface of water, will be

Air is streaming past a horizontal aeroplane wing such that its speed is $120\, m/s$ over the upper surface and $90\, m/s$ at the lower surface. If the density of air is $1.3\, kg/m^3$ and the wing is $10\, m$ long and has an average width of $2\, m$ , then the difference of the pressure on the two sides of the wing is ........ $N/m^2$

In a $U-$ tube experiment, a column $AB$ of water is balanced by a column $‘CD’$ of oil, as shown in the figure. Then the relative density of oil is

Water drop whose radius is $0.0015\, mm$ is falling through the air. If the coefficient of viscosity of air is $1.8 \times 10^{-5}\, kg/m-s$, then assuming buoyancy force as negligible the terminal velocity of the dorp will be