system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a particular shape coffee/tea cup that keeps the beverage hotter, longer?

I'm a pretty slow coffee drinker, so it tends to cool off quite a bit before I get to drink it all.  So, usually, it's not palatable by the time I get around to wanting to finish it off. I got to thinking this morning, is there a shape of cup in which the surface area or distribution of the drink would allow it to stay at a higher temperature over time?

I am fully aware that I can use a cup with a lid or a thermos, but I'm more so curious if anyone with a knowledge of Thermodynamics (or whatever field this would apply to) would have an answer to the best shape coffee mug for retaining temp and why it would do so.

Thanks!
gpt
Spherical. A sphere has the least amount of surface area per volume, and the surface is where the heat transfer happens. Less surface area means less heat transfer is possible. Since a sphere is not a practical shape for a mug, the cylinders we use now is probably the best comprimise.