Originally posted by Churchill
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Reply to: Electromagnets
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Previously on "Electromagnets"
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Do you factor in the increase in resistance as the temperature increases?Originally posted by doodab View PostI 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.
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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.
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Electromagnets
When doing your sums, remember it's 1.68 x 10 ^ -8. That factor of 100 million is quite important.Tags: None
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