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

  • UserFlairOptional@lemmynsfw.com
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    9 months ago

    Black-body radiation is an interesting argument against 100% efficiency, but couldn’t you just extrapolate and argue that the emission will be converted back to heat once it stops reflecting and becomes absorbed?

    • lemmyng@lemmy.ca
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      9 months ago

      That’s like arguing that trickle down economics is efficient because the money eventually gets into the hands of the poor.

      • Phil_in_here@lemmy.ca
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        9 months ago

        That’s like arguing that 99% of the light off a heating element is a laser beam directed straight into deep space.

    • ChonkyOwlbear@lemmy.world
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      9 months ago

      It depends on the framing of the question a bit. If we are defining 100% efficiency as 100% of electrical energy being converted into kinetic energy (heat) by the device, then that is a no. Some percentage is emitted as EM radiation instead of heat. If they were so then a light bulb or a bomb is a 100% effective heater as well.

      • CookieOfFortune@lemmy.world
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        9 months ago

        It depends on what you consider the room: Both a light bulb and a bomb would deliver all their energy around a fully enclosed room. Incandescent bulbs are indeed effective heaters, LEDs just deliver much less energy. And a bomb, by design, is hard to contain in a room.