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Please answer these two questions:

  1. Feb 8, 2006 #1
    hi Guys!

    well! i want to ask you people two very important questions:

    1) Why electrical energy is prefered over other forms of energies?

    2) What are electrical machines. If you think that electrical machines convert electrical energy into another form of energy or vice versa, please keep this in mind that a transformer is also called an electrical machine and that doesnot perform any conversion of energy in different forms.

    Thanks in advance
  2. jcsd
  3. Feb 8, 2006 #2


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    The first question doesn't make any sense without context. Obviously it isn't universally true, since the form of energy you want depends on what you are doing with it. Ie, when powering a car, you need mechanical energy.

    The second one also doesn't make a whole lot of sense. A lot depends on what definition of "machine" you want to use, so that really needs to be clarified.

    Are these homework questions?
  4. Feb 8, 2006 #3


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    What for? I don't prefer electrical energy to power my car, or to eat, or to carry around in my iPod.

    Ask yourself what a machine is, then answering your question will be easy. Are you trying to get us to do your homework?
  5. Feb 8, 2006 #4


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    Wow, those two posts are disturbingly similar - did we just prove the existence of telepathy?
  6. Feb 8, 2006 #5


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    High five Russ. Great minds think alike...
  7. Feb 8, 2006 #6
    Wow some people can’t just see a question from its basic perspective.
    They must add anomalies and expansions to the question which the question was never meant to have thus twisting the question into there own meaning and then answering there own representation of what was being asked. Henceforth never answering the original perspective the question was intended to ask.

    To answer question #1

    Electrical energy isn’t actually preferred over other sources of energy.
    It’s a requirement, think about this.

    People actually never get a valued opinion in what type of energy they want to use. People just let the major companies mass produce machines which use electrical energy.

    No poll is taken, no vote is cast, and no one is really saying...I want to use solar energy. Or hydro-energy, no one really says that...

    The majority of the population just kind of uses what the companies produce....
    So I wouldn’t call this a preference, its more of a prerequisite.

    Question 2) well your asking what a electrical machine is (if it where to convert electric energy into other forms of energy)

    To me this question to me is a hypothetical question, you are posing a theoretical situation and asking what you would classify a kind of machine
    Which runs on electrical energy and then converts it to different kinds of energy?

    Such as a windmill converting wind into a electric force, or Hydroelectricity
    But these machines aren’t really sub-atomically converting particles into different elements, these are energy extraction machines.

    So to answer your question (in theory)
    "What are electrical machines if you think that electrical machines convert electrical energy into another form of energy?"

    I would call them
    "Sub-atomic particle converters"
    Last edited: Feb 8, 2006
  8. Feb 8, 2006 #7


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    Agent, that's rubbish, sorry dude.

    To question one: If I was designing a brand new vehicle, I'd have a choice about what kind of energy I'd use to power it. I could ultimately use electrical, chemical potential, kinetic, or elastic potential energy to convert to kinetic energy to move my car. It's not a requirement, as such, that I use any one kind, but the best option comes from engineering decisions. Same goes for if I wanted to power my house by methane, or hamsters. I could do it, but would it provide the best engineering solution? Possibly not (although Danger would be able to bond with the hamsters).

    To question 2: There is a clearly stated definition of a machine, and adding 'electrical' as a prefix merely clarifies the context. In real terms, there's nothing sub-atomic about it.
    Last edited: Feb 8, 2006
  9. Feb 8, 2006 #8


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    Yeah agent, I'd say your post is B.S. You say no one has a choice of the type of energy. Someone obviously made a choice when the came up with whatever scheme they have going.
  10. Feb 8, 2006 #9


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    Agent C.I, solar vs hydro vs nuclear is still all electrical, just different ways to generate it. I'm quite certain that isn't what the OP was going for. And, as brewnog suggested, the decisions about which form to use to generate electricity (or move a car) are more a matter of engineering necessity than personal opinion.

    A link about the fundamental forms of energy: http://www.eia.doe.gov/kids/energyfacts/science/formsofenergy.html
    Last edited: Feb 8, 2006
  11. Feb 8, 2006 #10
    russ energy is the absolute basic element which must be inclined for anything to exist,....no matter what form energy comes in, it must be present for matter to even be able to form.

    What makes me laugh is you just posted a link which proves your statement wrong.....u just said every form of energy is electrical

    for the propose of education i will educate you in your inconsistencies.

    first and foremost each type of energy is different, identified according to the natural element it revolves around.

    Example russ
    Electrical Energy is the movement of electrical charges.
    The element this energy revolves around is in its most natural form is lighting

    However another form of energy runs on completely different principles
    Let’s take
    Chemical Energy is energy stored in the bonds of atoms and molecules. It is the energy that holds these particles together. Biomass, petroleum, natural gas, and propane are examples of stored chemical energy.

    the states of matter broken down into the form of gas & Liquids is the type of element chemical energy is revolving around.

    Now if u can’t learn from your own website...then lol
    Last edited: Feb 8, 2006
  12. Feb 8, 2006 #11


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    No, I did not. I said every form of energy in your post about ways electricity can be generated becomes electrical.

    Agent C.I, your contribution to this thread and your attitude toward other members has been pretty negative. Much of those posts is just incoherent gibberish. Please change that or I'm going to have to start editing/deleting your posts to maintain the quality level in this forum.
  13. Feb 8, 2006 #12
    Hello Guys!

    thanks a lot for your precious hot discussions. But i think that i should have clarified question 1 MORE.

    Well my dear friends, im just asking you in terms of entropy generation that which energy is more useful. Obviously, we cannot use electrical energy everywhere. But once i heard somwhere that electrical energy is an energy in whihc the entropy generation is least as compared to other forms of energy. That is the reason why its efficiency is very high. Is it correct? if not then please tell me why it is more useful.

    And please donot ask this question that is it my homework question. Im just asking you people some really confusing questions in my mind.

    I hope that you people love to help others.

    Thanks in advance

    Good Bye!
  14. Feb 8, 2006 #13
    and one thing more my dear friends!

    can anybody tell me what is the actual definition of an ELECTRICAL MACHINE.

    then why transformer falls in the category of the electrical machines?
  15. Feb 8, 2006 #14
    Any device that converts energy (or work) qualifies as a machine, the traditional example being a simple lever: it converts a force applied over a distance into a different force applied over a different distance. Actually the forces and distances can be the same, but the work is indeed transfered by this simple machine. Likewise, a transformer is also a machine: it converts a certain voltage and current into a different voltage and current. So my definition of a generic electric machine would be one that converts work into equivalent work where one or both of these is electrical.
  16. Feb 8, 2006 #15


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    You mean, is electrical energy more efficient somehow than other forms? Again, it depends on the application and more importantly, the way the engergy is converted from one form to another. Entropy/efficiency losses all arise from conversions, whether it be a conversion between different forms of electrical or from electrical to something else.

    It is true that electrical to electrical and electrical to heat conversions are quite efficient, but there are many examples (such as heat or EM to electrical) of conversions that are not very efficient at all. And the converse is true for things like chemical to heat (though not heat to mechanical) - the furnace in your home may only be 85% efficient, but that is only because you are exhausting waste gases. The actual energy conversion from chemical to heat is 100% efficient. So again, I'd say you need to take that idea on a case-by-case basis.
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