| Reminds me of the units used for vehicle fuel efficiency: litres per 100 km. But liters is a unit of volume (length x length x length) and kilometers is a unit of distance (length). Hence, this efficiency metric is equivalent to L^3/L or just L^2. That is, the unit of vehicle fuel efficiency is a measure of area! The area of what, you ask? If you made the contents of your tank into a long thin stream of fuel as your vehicle moved along, then its cross section is the instantaneous fuel usage. You can imagine your car driving along, "sucking up" this long thin streamer of fuel as it moves.[1] The thicker this line of fuel, to more it needs for the same distance. My car gets about 7L/100km, which works out[2] to just 0.07 mm^2, which is surprisingly thin! [1] I can't take credit for this concept, I got it from XKCD's What If section: https://what-if.xkcd.com/11/ [2] https://www.wolframalpha.com/input?i=7+L+%2F+100+km+in+mm%5E... |