What is viscosity?

Viscosity is a measure of a fluid's resistance to flow. It describes the internal friction of a moving fluid. A fluid with large viscosity resists motion because its molecular makeup gives it a lot of internal friction. A fluid with low viscosity flows easily because its molecular makeup results in very little friction when it is in motion.
Gases also have viscosity, although it is a little harder to notice it in ordinary circumstances.

JN

Related Physics A Level answers

All answers ▸

A stationary observer Bob, observes Alice take 5 seconds to travel from point A to B at 0.95c. How much time does Alice measure the journey from A to B to take?


A sigma0 particle with mass 1193 MeV/c^2 decays into a lambda0 particle with mass 1116 MeV/c^2 a photon. Find the energy and momentum of the photon, assuming that the kinetic energy of the lambda0 particle is negligible.


Show that a mass on a spring obeys simple harmonic motion.


A child is standing on a walkway that is moving at 2 metres per second and decides to turn around and walk back to the start at 2 metres per second. Explain why the child cannot reach the start of the walkway at this speed.