Fietsen om warm te worden
Geplaatst: vr 07 dec, 2012 10:41
Voor het antwoord: http://what-if.xkcd.com/23 (onderaan)I bike to class sometimes. It's annoying biking in the wintertime, because it's so cold. How fast would I have to bike for my skin to warm up the way a spacecraft heats up during reentry?