Joshua Cude <> wrote:

> With 1 kW, you can raise the temperature of the water at 300 mL/min about
> 50C to give 65C or so, definitely too hot to touch.

That is true, but the power was not 1 kW. It was 400 W. It was 1 kW at the
beginning of the experiment, but a flow calorimeter or hot water heater
cools down rapidly at these flow rates, so a few minutes after the power
falls to 400 W, the water would be lukewarm.

In Japan, most kitchen and bathroom sink water heaters are the instant,
on-demand type that heat up the water as it flows through. Essentially, they
are flow calorimeters. A recalcitrant old gas fired one that I use often
goes off and stays off as the water is flowing. The water cools down
instantly. (Come to think of it, that's kind of dangerous. We should
probably get it replaced.)

- Jed

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