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Science project how does voltage travel

I am doing a science project and I'm looking for research on how does voltage travel.

Monica [last name deleted for privacy by Editor]
- Chicago, Illinois, USA
2002

It doesn't, Monica. Voltage is analogous to water pressure; it causes current to flow. Without knowing what grade you are in, it's a bit hard to explain how current flows (what you learn in high school will be a simplification that will be countermanded in college courses). But for high school purposes, current flows by electrons traveling along a wire.

However, since this is a metal finishing site, and many students pose questions here because they intend to do electroplating, we should note that electricity can also travel via ions (charged particles) moving through a solution.

Please try your school or town librarian for a grade-appropriate text on this. Asking people on the Internet really isn't a good substitute for an appropriate science book. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002

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Ted is right. Voltage does not flow, it is the force needed to pass the current through the conductor, which in reality has a resistance and wants to stop the electricity flowing. The bit of electricity that flows is the current and this is passed by the transfer of electrons from one atom to another. Some atoms or molecules (such as metals or many liquids such as impure water) are quite amicable to doing this whilst others, like plastics are not at all keen. The greater the reluctance to let the electrons jump from atom to atom is a measure of the insulation of the material. Where electrical flow is concerned, think of the electricity as a river going through a narrow; the amount of water going through (say in gallons per second) is equivalent to the current, whilst the force exerted on the water to make it go through is the voltage and the amount the river is restricted is the resistance. Then bring in Ohms Law (By far THE most important equation in electrical studies) and you get: V = IR, where V = volts, I = current and R = resistance

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2002