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The instant consumption of electric cars can be measured as kW which is power, but the overall consumption will more commonly use something like kWh/km which is a force unit (equal to 3600 N); and the ratio between the two is the average speed measured in km/h.

Is this related to the answer of your original question?

[Yes technically you'd more likely see kWh/100km or Wh/km, but the result is a silly unit for speed].



Yeah it gets to the kind of weirdness that a kWh has the same dimensions as a Joule: power is an instantaneous measurement and when integrated over time yields energy: (mass * distance) / (time squared) vs (mass * distance) / (time), to use the engineering sense of d / dt meaning "dividing by a little bit of t" (we were supposed to avoid saying that around people from the mathematics department).

Where it got really interesting was Heisenberg, because the indeterminance relationship doesn't just hold for position and momentum but for any two units whose dimensions multiply out to (mass * distance squared) / (time). So famously meter vs kilogram * meter / second, but more usefully in real life second vs Joule. Or weird combos like mass vs change in area over time, whatever that would mean...




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