How long can a glass cup keep hot water warm?

Answer:
It would depend on the temperate of the room, the amount of water, the temperate of the hot water and the thickness of the glass. (Also on the humidity, the elevation)

So it's really impossible to say.

I assume you mean a typical 250 ml glass, and the air was room temperate, normal pressure, humidity, fairly typical elevation...
But, I'm still not sure what temperate of water you mean, which is one of the most important factors.

30 minutes perhaps?
First answer by ID1260571209. Last edit by Ben Chiasson. Contributor trust: 3 [recommend contributor recommended]. Question popularity: 1 [recommend question].