What is viscosity?

Based on the given figure, the number of correct statement/s is/are

A. Surface tension is the outcome of equal attractive and repulsion forces acting on the liquid molecule in bulk.

B. Surface tension is due to uneven forces acting on the molecules present on the surface.

C. The molecule in the bulk can never come to the liquid surface.

D. The molecules on the surface are responsible for vapour pressure if the system is a closed system.

Glycerine flows steadily through a horizontal tube of length $1.5 \mathrm{m}$ and radius $1.0 \mathrm{cm}$. If the amount of glycerine collected per second at one end is $4.0 \times {10}^{-3} \mathrm{kg} {\mathrm{s}}^{-1}$ , what is the pressure difference between the two ends of the tube? (Density of glycerine $= 1.3 \times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$ and viscosity of glycerine $= 0.83 \mathrm{Pa} \mathrm{s}$). [You may also like to check if the assumption of laminar flow in the tube is correct]. 

If the equal and opposite deforming force are applied parallel to the cross-sectional area of the cylinder as shown in the figure, there is a relative displacement between the opposite faces of the cylinder.

The ratio of $∆x$ to $L$ is known as

In deriving Bernoulli’s equation, we equated the work done on the fluid in the tube to its change in the potential and kinetic energy. Do the dissipative forces become more important as the fluid velocity increases? Discuss qualitatively.