Need Help on the science fair

[Lwilfredo4]

What is the effect of voltage on the strength of an electromagnet?

[Jim Lewandowski]

Howdy,
The question you should be asking is, what is the effect of "current" on strength of an electromagnet. The amount of current will vary with voltage, in a simplistic form by Ohm's Law, V=I*R. Where "R" is the resistance, or of the wires. Most conductive wire has a very low resistance and you will need to wind a lot of wire in order to get an effective resistance.

Where I work we think in terms of varying the current through a magnet to change its field.

The magnetic field generated will depend on your core material, and the number of times you wrap the wire around the core.

Many simple experiments use a nail and some wire to do the experiment, it may be easier to take data if you were to keep the voltage constant and vary the number of turns and demonstrate the difference in field strength.

Here is an example of a "solenoid" magnet that has no core, just wire coils, it is also the basic form of inductors..
http://hyperphysics.phy-astr.gsu.edu/hb ... id.html#c1



Are you going to make an electromagnet? What materials do you have?

Jim