A very thin thread of coloured dye is released at the centre of water flowing…
PHYSICS · Single correct · AP · Physics 1: Algebra-based · Fluids · Fluids
Problem
A very thin thread of coloured dye is released at the centre of water flowing steadily through a transparent horizontal tube. As the flow speed is gradually increased, which observation indicates that the flow has just become turbulent?
(a) The dye thread contracts further and becomes brighter in colour.
(b) The dye thread remains narrow and straight in the centre of the tube.
(c) The dye thread widens and breaks up into irregular swirls filling the tube.
(d) The dye thread shifts uniformly towards the wall and stays intact.