Viscosity of a liquid - Stoke's method

Which property measures the resistance of a liquid to flow ?

• Volume

• Viscosity

• Solubility

• Density

Which of the following is the correct statement?

• All of the above

• Both liquids and gases exhibit viscosity

• Viscous force is the force offered by the adjacent liquid layers

• Viscous force is a frictional force

The rain drops falling from the sky neither hit us hard, nor make holes on the ground. Why?

• Because they move with a constant velocity

• Because they move with a variable speed

• Because they move with a variable acceleration

• Because they move with a constant acceleration

Two balls whose radii are in the ratio 1:2 fall from a height of 50 km. What will be the ratio of their terminal velocities ?

• 4:1

• 1:9

• 1:4

• 9:1

What is the unit of coefficient of viscosity?

• N/m^2

• Nsm^-2

• Nsm^2

• None of these

Cooking oil appears to move more fluidly upon a frying pan after being heated on a stove. Why?

• Viscosity decreases with increase in temperature

• None of these

• Viscosity becomes zero as the temperature increases

• Viscosity of oil increases with increase in temperature

Which of the following factors are responsible for the viscous force acting on a spherical body?

• Terminal velocity of the spherical body

• Coefficient of viscosity of the liquid

• All the above

• Radius of the spherical body

What happens to the viscosity of a liquid when pressure increases ?

• Decreases

• Become zero

• Remains constant

• Increases

Choose the incorrect statement from the following.

• Coefficient of viscosity does not depend on terminal velocity.

• Viscous force acts in opposite direction of velocity.

• Coefficient of viscosity depends on density of the liquid.

• Viscous force is directly proportional to terminal velocity.