# How to generate a magnetic field

1. Jan 30, 2012

### androsidhom

dear all
i am trying to generate a magnetic field of intensity about 10 k A/m i have i 1 mm copper wire and a power supply 12v DC 18 amp max, i am winding the coil about 100 turn- 10 layers ( each layer with two ends)
the first problem that the coil heats up, also the resistance of the each layer is about 1.2 Ω and when i connect the solenoid to the power supply it makes a short circuit to the power supply
my questions are
1- is this no of turns and the amp available is sufficient to generate this intenisty of the magnetic field?
2- how to over come the short circuiting of the power supply?
3- how to over come the over heating of the solenoid?
4- is it much better to make the solenoid all connected together without separating each layer?

2. Jan 30, 2012

### Drakkith

Staff Emeritus
1. This link should get you the equations and stuff you need to calculate your field. http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html#c3

2. You could try adding a resistor in the circuit or using a current limiting power supply.

3. Less current will reduce the heating, as would using a larger wire, as that would decrease the resistance. If you have no choice you could try to force air over it with a fan or water cool it. (Warning, be VERY careful about using water cooling to avoid a short.)

4. I'm not sure what you mean. Why are the layers seperated? Is your wire coated with an insulating material, or are you using bare copper wire?