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Reply to: Electromagnets

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Previously on "Electromagnets"

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  • doodab
    replied
    Originally posted by Churchill View Post
    What about thermal shock?

    Calm down man, I've not even got the knack of ohms law yet!

    Leave a comment:


  • Churchill
    replied
    Originally posted by doodab View Post
    I think it's safe to say my mathematical models are not that sophisticated
    What about thermal shock?

    Leave a comment:


  • doodab
    replied
    Originally posted by Churchill View Post
    Do you factor in the increase in resistance as the temperature increases?
    I think it's safe to say my mathematical models are not that sophisticated

    Leave a comment:


  • Churchill
    replied
    Originally posted by doodab View Post
    I have to chuckle when I see that someone left me a -ve rep for my "pointless post" at 1am.

    Go to bed you freak!

    It's not pointless, the number up above is the resistivity of copper, an essential ingredient in calculating the current through your solenoid and the resulting heat emission. Leaving the aforementioned factor of 100 million out of your calculation causes you to overestimate the resistance of the coil and hence underestimate the current by a large factor. Which means it doesn't work quite as you expect.

    If I can save one innocent battery from death it's worth it.
    Do you factor in the increase in resistance as the temperature increases?

    Leave a comment:


  • doodab
    replied
    I have to chuckle when I see that someone left me a -ve rep for my "pointless post" at 1am.

    Go to bed you freak!

    It's not pointless, the number up above is the resistivity of copper, an essential ingredient in calculating the current through your solenoid and the resulting heat emission. Leaving the aforementioned factor of 100 million out of your calculation causes you to overestimate the resistance of the coil and hence underestimate the current by a large factor. Which means it doesn't work quite as you expect.

    If I can save one innocent battery from death it's worth it.
    Last edited by doodab; 24 May 2011, 06:10.

    Leave a comment:


  • doodab
    replied
    Originally posted by PRC1964 View Post
    Worse than that, he's 18.
    Is that leet for "works at goldman sachs"?

    Leave a comment:


  • PRC1964
    replied
    Originally posted by doodab View Post
    Is he dyslexic? Or does he just have something stuck in his throat?
    Worse than that, he's 18.

    Leave a comment:


  • doodab
    replied
    Originally posted by PRC1964 View Post
    kthxbai to borrow from my 18 year old nephew.

    Newspeak is 2xgd
    Is he dyslexic? Or does he just have something stuck in his throat?

    Leave a comment:


  • PRC1964
    replied
    kthxbai to borrow from my 18 year old nephew.

    Newspeak is 2xgd

    Leave a comment:


  • doodab
    started a topic Electromagnets

    Electromagnets

    When doing your sums, remember it's 1.68 x 10 ^ -8. That factor of 100 million is quite important.

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