Electromagnet did not Work

Most recent answer: 05/16/2013

Q:
Inorder to construct an electromagnet I took a long iron nail and wrapped an insulated as well as a non insulated copper wire and connected the copper wires to a 12 volts adapter.But when I switched on the current and kept a blade near it I saw no magnetism produced and there is no effect on the blade.Are there any other requirements to complete this electromagnet.
- Prudhvi Raj Borra (age 16)
Machilipatnam,Andhra Pradesh,India.
A:
There could be several reasons:
The blade was made of stainless steel which is not attracted to magnets.
The 12 Volt adapter had a current limit that was insufficient.
Not enough turns in the coil.

Try to measure the voltage across the coil to see if it is holding up.
Try to measure the DC current. 
Use some iron filings instead of the knife as a test attractant.

LeeH

p.s. And stick with the insulated wire. The other will short out and not give you any current looping around the nail. Mike W.


(published on 05/16/2013)