Hello,(adsbygoogle = window.adsbygoogle || []).push({});

A few days ago I read a story in the newspaper.

In a cityblock the voltage of the grid was accidently increased to 400V (instead of the standard 240V).

Clearly quite a few appliances died because of this.

My question is how far can I get explaining these breakdowns using Ohm's law and the Joule effect.

Basically an explanation at the high school level.

If we simply replace the device by a resistor it is clear that through ##P=\frac{U^2}{R}## we get a lot more power that has to be dissipated.

From this we can expect the resistor to melt if we simplify the system in an extremely naive way.

Thanks,

Joris

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# Broken devices due to increased voltage

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