Which of the following best describes the microscopic origin of the pressure exerted…
PHYSICS · Single correct · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
Which of the following best describes the microscopic origin of the pressure exerted by a fluid on the walls of its container?
(a) The weight of the fluid above each surface pushes downward and is redirected sideways by the walls.
(b) The random motion of molecules parallel to the surface produces shear stresses that are felt as pressure.
(c) Momentum changes during countless random molecular collisions with the container’s surface produce a net perpendicular force per unit area.
(d) Cohesive intermolecular forces pull molecules inward, squeezing the fluid against the walls.