A liquid does not wet the solid surface if the angle of contact is:
1. equal to $\mathrm{}$\(45^{\circ}\)
2. equal to \(60^{\circ}\)$\mathrm{}$
3. greater then \(90^{\circ}\)$\mathrm{}$
4. zero 

A barometer is constructed using a liquid (density = \(760~\text{kg/m}^3\)). What would be the height of the liquid column, when a mercury barometer reads \(76~\text{cm}?\) 
(the density of mercury = \(13600~\text{kg/m}^3\))

A barometer is constructed using a liquid (density = 760 kg/${\mathrm{m}}^3$). What would be the height of the liquid column, when a mercury barometer reads 76 cm? (density of mercury = 13600 kg/${\mathrm{m}}^3$)

(1) 1.36 m

(2) 13.6 m

(3) 136 m

(4) 0.76 m

A liquid does not wet the solid surface if the angle of contact is :

(1) equal to 45°

(2) equal to 60°

(3) greater than 90°

(4) zero

A capillary tube of radius \(r\) is immersed in water and water rises in it to a height \(h.\) The mass of the water in the capillary is \(5\) g. Another capillary tube of radius \(2r\) is immersed in water. The mass of water that will rise in this tube is:

In a U-tube, as shown in the figure, the water and oil are in the left side and right side of the tube respectively. The height of the water and oil columns are \(15~\text{cm}\) and \(20~\text{cm}\) respectively. The density of the oil is: 
\(\left[\text{take}~\rho_{\text{water}}= 1000~\text{kg/m}^{3}\right]\)$$

Two small spherical metal balls, having equal masses, are made from materials of densities \(\rho_1\) and \(\rho_2\) such that ${}_{}$\(\rho_1=8\rho_2\) and having radii of \(1\) mm and \(2\) mm, respectively. They are made to fall vertically (from rest) in a viscous medium whose coefficient of viscosity equals \(\eta\) and whose density is \(0.1\rho_2\)${\mathrm{}}_{}$. The ratio of their terminal velocities would be:

A soap bubble, having a radius of \(1~\text{mm}\), is blown from a detergent solution having a surface tension of \(2.5\times 10^{-2}~\text{N/m}\)$$. The pressure inside the bubble equals at a point \(Z_0\) below the free surface of the water in a container. Taking \(g = 10~\text{m/s}^{2}\)${\mathrm{}}^{}$, the density of water \(= 10^{3}~\text{kg/m}^3\)${\mathrm{}}^{}$, the value of \(Z_0\) is:
1. \(0.5~\text{cm}\)
2. \(100~\text{cm}\)
3. \(10~\text{cm}\)
4. \(1~\text{cm}\)