Tea is not very viscous (as in it is not very thick/sticky consistency) so when you turn the cup, the liquid stays in place, while the outer rim (the cup) rotates. If you did the same thing with a cup of honey, the hair would rotate. You can make the hair rotate in tea by doing repeated circular motion movements (imparting rotational momentum in the liquid over time) or by rotating the cup really slowly so that the liquid flow doesn't detach from the surface.
cfhalcyon t1_iu4pkcb wrote
Reply to I was drinking tea and got a hair in it. I rotated the cup but the hair seemed like it was stationary even though I was rotating the cup thinking it would then be on the opposite side of the cup away from my mouth. Why does the hair not rotate along with the cup? by Nomorethisplz
Tea is not very viscous (as in it is not very thick/sticky consistency) so when you turn the cup, the liquid stays in place, while the outer rim (the cup) rotates. If you did the same thing with a cup of honey, the hair would rotate. You can make the hair rotate in tea by doing repeated circular motion movements (imparting rotational momentum in the liquid over time) or by rotating the cup really slowly so that the liquid flow doesn't detach from the surface.