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Read the passage given below and answer the following questions from $1$ to $5$. Surface Tension The property due to which the free surface of liquid tends to have minimum surface area and behaves like a stretched membrane is called surface tension. It is a force per unit length acting in the plane of interface between the liquid and the bounding surface i.e., $\text{S}=\frac{\text{F}}{\text{L}},$ where F = force acting on either side of imaginary line on surface and L = length of imaginary line. Surface tension decreases with rise in temperature. Highly soluble impurities increases surface tension and sparingly soluble impurities decreases surface tension.

1. The excess pressure inside a soap bubble is three times than excess pressure inside a second soap bubble, then the ratio of their surface area is:

1. 9 : 1
2. 1 : 3
3. 1 : 9
4. 3 : 1

2. Which of the following statements is not true about surface tension?

1. A small liquid drop takes spherical shape due to surface tension.
2. Surface tension is a vector quantity.
3. Surface tension of liquid is a molecular phenomenon.
4. Surface tension of liquid depends on length but not on the area.

3. Which of the following statement is not true about angle of contact?

1. The value of angle of contact for pure water and glass is zero.
2. Angle of contact increases with increase in temperature of liquid.
3. If the angle of contact of a liquid anda solid surface is less than 90°, then the liquid spreads on the surface of solid.
4. Angle of contact depend upon the inclination of the solid surface to the liquid surface.

4. Which of the following statements is correct?

1. Viscosity is a vector quantity.
2. Surface tension is a vector quantity.
3. Reynolds number is a dimensionless quantity.
4. Angle of contact is a vector quantity.

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

1. 0°
2. Equal to 90°
3. Equal to 45°
4. Greater than 90°