How can i calculate the resistance of this electromagnet?

AI Thread Summary
To estimate the resistance of the electromagnet, the seller's listing indicates it uses 5 watts and operates at 12 volts. Using the formula 5 watts = 12 volts^2 / Resistance can help calculate the resistance. The current specification of 0.42A allows for an alternative calculation using Ohm's Law, where resistance equals voltage divided by current. Both methods should yield the same resistance value. This approach provides a practical way to determine the electromagnet's resistance based on available specifications.
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berkeman said:
It looks like the picture has some light words across it -- KIMKE something. Could that be the manufacturer? Otherwise, can you e-mail the seller and ask if they know, or if they have a datasheet?
The ebay post says the electromagnet uses 5 watts, can i plug that into the equation, 5 watts = 12 volts^2 / Resistance ??
 
radaballer said:
The ebay post says the electromagnet uses 5 watts, can i plug that into the equation, 5 watts = 12 volts^2 / Resistance ??

Yeah, good idea. :smile:
 
Current is listed as 0.42A in the specs. So you could also divide voltage by current (simple ohms law). Same result.
 

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