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Homework Help: Any Physics experts out there?

  1. Jan 23, 2009 #1
    I need a little help on a few questions that came up in my physics book..I have an exam soon, so I'm trying to get all the help I can possibly get. :smile:

    What is the similarity between a galvanometer and a simple electric motor?

    ????? I'm really stuck on this one.

    How can a magnet attract a piece of iron that is not magnetized?

    For this one, I think the fact that iron contains magnetic domains (which are atoms with north and south poles) has a lot to do why there is an attraction. Need more clarity though.

    How does the electric company use a transformer to moderate your house current?

    The answer of this question revolves around the transformers principle, which is when change occurs in the magnetic fields of current-carrying coil of a wire that is intercepted by the second coil of wire, which in the end induces voltage in the second coil.

    What I need more clarity on is how the exchange happens.

    Thanks. :biggrin:
    Last edited: Jan 23, 2009
  2. jcsd
  3. Jan 23, 2009 #2


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    Staff: Mentor

    Welcome to the PF. I moved your thread from Advanced to Intro Physics (Advanced is more for upper division and graduate level questions).

    On the first one, can you describe for us what each of those devices is, and how they work?

    On the second one, have you studied what electric dopoles do in a non-uniform Electric field? The situation is analogous to the magnetic question they are asking, and you are sort of on the right track with your attempt at a solution

    On the third question, it's not worded very well. Is that the exact question? The electric company uses transformers to change voltage levels for long-distance transmission for a specific reason. Maybe try a search at wikipedia.org on "electric transmission line" or similar to see if you can spot the reason....
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