this post was submitted on 17 Feb 2024
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Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.

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If a machine is never 100% efficient transforming energy into work because part of the energy is converted into heat, does it mean an electric heater is 100% efficient? @showerthoughts@lemmy.world

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[–] addie@feddit.uk 26 points 8 months ago (2 children)

The sound will eventually dissipate in the air as heat. The light will be absorbed into surfaces, like any other radiation, as heat. Still 100%, but with a couple extra stops along the way.

[–] kakes@sh.itjust.works 3 points 8 months ago (1 children)

All energy output will eventually become heat. Why bother measuring efficiency at all if we're counting those aftereffects?

[–] pixxelkick@lemmy.world 7 points 8 months ago (1 children)

Only heaters are a machine where the "good" output is one you want to be heat.

For other devices the heat is the bad part.

But since your goal with a heater... is to generate heat... and all energy eventually will become heat, it is close to 100% efficient.

If you can hear the heater's sound it makes in a room/area you don't want to be heating though, now it's <100% efficient as a tiny bit of energy became heat that heated the non ideal location.

[–] kakes@sh.itjust.works 3 points 8 months ago

Fun fact: this phenomenon is what causes the infamous "hot ear" effect that many people suffer from every day.

[–] CookieOfFortune@lemmy.world 2 points 8 months ago

Yeah I mean you’d have to consider the practical factors such as how quickly or evenly they can heat up a room rather than worry so much about the raw efficiency.