When a large bubble rises from the bottom of a lake to the surface, the volume of the bubble becomes $5$ times its volume at the bottom of the lake. If $H$ is the atmospheric pressure expressed in terms of water column height, then the depth of the lake is (The temperature of the water in the lake is same at all points). (in $H$)

An air bubble rises from the bottom of a water tank of height $5 \ m$. If the initial volume of the bubble is $3 \ mm^3$, what will be its volume as it reaches the surface (in $mm^3$)? Assume that its temperature does not change. $[g=9.8 \ m \ s^{-2}, 1 \ atm=10^5 \ Pa, \text{density of water}=1 \ g/cm^3]$

Statement $(A)$: When the temperature increases,the viscosity of gases increases and the viscosity of liquids decreases.
Statement $(B)$: Water does not wet an oily glass because the cohesive force of oil is less than that of water.
Statement $(C)$: $A$ liquid will wet a surface of a solid if the angle of contact is greater than $90^{\circ}$.

$A$ cylindrical vessel partially filled with water is rotated about its vertical central axis. Its surface will

The vessel shown in the figure has two sections. The lower part is a rectangular vessel with area of cross-section $A$ and height $h$. The upper part is a conical vessel of height $h$ with base area $A$ and top area $a$,and the walls of the vessel are inclined at an angle $30^o$ with the vertical. $A$ liquid of density $\rho$ fills both the sections up to a height $2h$. Neglecting atmospheric pressure:

$A$ drop of water detaches itself from the exit of a tap when $(\sigma=$ surface tension of water, $\rho=$ density of water, $R=$ radius of the tap exit, $r=$ radius of the drop $)$