How do I test Ohm's law using a homemade circuit or circuits?

I'm doing this for school project. I've constructed a simple circuit using wire, battery, paper clip, and a lightbulb. Now I want to cal-

culate resistance using this circuit to test Ohm's law. I want to

know what procedure to do and what materials needed to do this. Please help if you can. Thank you.

You need some test equipment, such as a voltmeter and ammeter.

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Ohm's Law:

V = I * R

One thing to carefully consider is that this is for a specific instance in time. If you use AC (varying current and voltage) it gets a bit more complicated so for this experiment I would recommend you stick with a DC source (like a battery) rather than an AC source (house electrical power). Also it is a lot safer. Your heart is very sensitive 60Hz AC so electrical power can easily kill you.

So ... To test Ohm's law you need some way to measure I, V, and R then make sure they match the equation. Let me take those one at a time:

V: You need to either measure this (the best choice) or at least know it's value. If you can borrow or buy a multimeter, You can get one for under $20 from Home Depot, Lowe's, or Radio Shack.

I: This one you pretty much have to measure using a multimeter. Make sure you stay under the rating for the meter or you will blow its fuse (or it) up.

R: Measure this with your multimeter or use one with a known value. You can get resistors at Radio Shack for under $1.

Warning: While Ohm's law will work for a light bulb (on any electrical load), the resistance of a light bulb changes as the light bulb heats up so the resistance when you measure it with the meter (cold) will not be the same is it will be once current is passing through it (warm/hot) so it will not appear to follow Ohm's law (but it really is).

Goo Luck