Surface Tension 1

If the surface of a liquid is plane, then the angle of contact of the liquid with the walls of the container is

• 90⁰

• 0⁰

• Acute angle

• Obtuse angle

Which of the following is not an effect of surface tension

• Capillary rise

• Spherical shape of water drops

• Spiders skirting on water

• Cylindrical shape of water drops

A soap bubble contains two surface layers. What is the excess pressure just inside the first layer when seen from outside the bubble?

• S/R

• 2S/R

• 4S/R

• S/2R

The Unit of surface tension is

• Nm

Which has an obtuse angle of contact

• Mercury

• Water

• Suplpuric acid

• Oil

A mercury drop of radius 1 cm is broken into 10⁶ droplets of equal size. The work done is

• 4.35 × 10^-2 J 

• 4.35 × 10^-3 J

• 4.35 × 10^-6 J 

• 4.35 × 10^-8 J

The energy needed in breaking a drop of radius R into n drops of radius r is

The dimensional formula of surface tension is

The surface tension of water can be reduced by

• heating

• Adding a detergent

• cooling

• None of these methods will decrease surface tesnion

How do you feel about your upcoming examinations

• Confident

• Tense

• Cannot say