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How do I get electricity started with just a wire, battery, and a light bulb. I need it for a project I have to do. I always thought wire doesn't have enough power to light a light bulb.
Question Date: 2003-03-25
Answer 1:

The electricity to light your light bulb comes from the battery - the wire is what the electricity moves through.

An important thing to consider is how the battery works. There is a chemical reaction inside that puts extra electrons at the + terminal. When a wire goes from the + side to the - side, the electrons flow through it to go the - side.

If your light bulb is in the middle of the wire, the electrons will flow through the light bulb as well, causing it to light up. So to do this in your case, you actually need two wires. One wire will go from the + side of the battery to one side of the light bulb, the other will go from the other side of the light bulb to the - terminal.

Answer 2:

The power for the light bulb does not come from the wire - it comes from the battery. The wire simply provides the conducting path. Your teacher gave you only ONE wire? haha - this is a tricky question , but you can still light the bulb. I bet you think you have to have TWO wires, right? So that you connect one wire between the battery and bulb on each side - well, you can do it with only one wire! Here's how:

Look carefully at your battery - it has two terminals, a positive and a negative. On most batteries the positive terminal sticks out a bit, and the negative one is flat, or pushed in just a little bit. That way you can tell which is which. The positive is where the positive charge carriers come out, full of ELECTRIC POTENTIAL ENERGY and the negative is where they come back in, after doing their "work", to get re-energized by the battery.

Now look at your bulb - it has two terminals also, but they are a bit hidden.

One terminal is where you would expect it: at the tip of the bulb (the metallic pointy tip, not the glass bulb). The other one is not so obvious:

it is WRAPPED AROUND the base of the bulb! If you look carefully at your bulb, you will see a thin black or dark colored plastic ring that separates the bottom metallic point of the bulb and the metal collar that is wrapped around - that's the insulation.

Now here's how to light your bulb with only one wire and one pair of hands (yours):

First strip off a few inches of the insulation from one end of the wire very carefully, so as not to cut the copper strands beneath the thin plastic insulation. Then wrap the bare wire securely around the collar of your bulb (one terminal). Then touch the other end of your wire to EITHER the positive or negative terminal of your battery, and AT THE SAME TIME touch the tip of your bulb to the OTHER terminal of your battery.

This will light your bulb - if it does not light, try tightening the wire around the collar of the bulb. If you have small hands and a big battery (like a D cell) you might need the assistance of another pair of hands to make the connections tight enough. Try reversing the terminals - it does not matter which direction you connect, as long as you have a complete CLOSED CIRCUIT. But this will work - the battery is lighting the bulb - the wire just makes a conducting path. In principle, if you had a long, skinny, flexible battery you could just touch one terminal of the battery to the tip of the bulb and the other to the wire collar, and the bulb would light up.

Touch one end of the wire to either terminal of your battery; touch one terminal of your bulb to the other end of the wire.

Here's a good source on line about how bulbs work:
light bulb

Answer 3:

Depending on the properties of the battery, wire, and light bulb you should be able to get the light bulb to light up by creating a current loop.

To do this, you could hook up one end (positive or negative) of the battery to one of the inputs on the light bulb with some wire and hook up the other pole of the battery to the other input to the light bulb. This will allow current to flow from the positive side to the negative side of the battery through the wire inside the light bulb that heats up and generates light . The light bulb needs a certain amount of power (voltage times current) to light up so you need to make sure that your battery can put out enough current. You should also make sure that your wires are thick enough to allow current to flow easily.

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