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Detecting Energy

  1. Feb 23, 2007 #1
    Can we only detect energy by its effect on matter? i.e. we detect temperature because it makes the mercury move, sun’s heat because it makes us feel warm, etc.

    In other words, does energy really exist beyond inductive reasoning?
  2. jcsd
  3. Feb 24, 2007 #2


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    What do you have in mind?
  4. Feb 24, 2007 #3
    My intention is not to disprove energy or anything, I firmly believe in science, energy and matter. I do want to see if this is the prevailing consensus so I can sort some things out with a philosophical argument I have.

    I can go into the philosophy in another thread under the correct forum, but right now that is not what I have planned. I'm really just looking for an answer to this simple question. Or is this question not so simple?

  5. Feb 24, 2007 #4
    A further clarification…

    I guess what I’m asking is if anything is really known outside of people observing matter changing. We can’t see energy or really know its properties unless we can look at the pattern in which it changes matter. Is this correct?
  6. Feb 24, 2007 #5
    Can I request to the moderator to move this thread to the Philosophy forum?

  7. Feb 24, 2007 #6


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    "Matter changing" is [a clumsy way of saying] what energy is, so the answer is a clear yes. Dropping a rock from a certain distance, for example. You can see the rock and you can see the distance. That's potential energy. Drop it and it falls. That's kinetic energy.

    Do you drive? How do you tell how much braking force is required to stop your car in a certain distance? Through practice, you get an intuitive feel for the amount of energy there is in a certain speed.

    And no, this isn't philosophy. Energy has a clear physical meaning.
    Last edited: Feb 24, 2007
  8. Feb 25, 2007 #7


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    Energy is just a quantity that stays constant during the movement of the object. different kinds of energy are ways of calculating this quantity in different situations. since it is conserved, it's harder to make a big change in the energy than a small one (it's harder to stop a fast car than a slow one).

    And anyway, how can you measure something without it affecting the instrument that you're measuring with.
  9. Feb 25, 2007 #8
    So my philosophical point is that from the Human consciousness point of view, energy relies on matter to exist. If there was no matter to perform work on, then energy as we know it cannot exist. If the universe ends up in Heat Death – all matter being converted into energy, then there is nothing to apply force to. Anything wrong with this reasoning?

    Though matter and energy do exist from our point of view... And this is one of the arguments of my philosophy.
    Last edited: Feb 25, 2007
  10. Feb 25, 2007 #9

    Thanks for reminding me why I can't stand philosophy.
  11. Feb 25, 2007 #10


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    No. There are other forms of energy, like electromagnetic.
    No, except for the part where it contradicts itself.... :biggrin: You just mentioned a heat death where everything is energy, yet above you said energy depends on matter.

    Anyway, I don't see any philosophy here.
  12. Feb 25, 2007 #11


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    This thread has strayed into something that is neither physics nor philosophy (nor does it fit with any other topics on this site). Therefore, it is locked.
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