Perfect Wire

Perfect Wire
What is a ground wire?

What is so important about a groundwire? Why can a car electronic device such as an amplifier only run off a power wire? Why is it so important to have this wire hooked onto a peice of metal? Please explain it to me. Its so hard to find the perfect grounding spot.

DC used in cars stands for Direct Current is defined as current that travels in only one direction most theorys suggest (+) to (-) AC used in both home and car Alternating Current is an electrical current that periodically changes polarity in a car the altinator creates AC that is changed into DC by a prosses called rectification. For any electronics to be a closed curcuit there needs to be a power sourse and a return or a ground. Its important to have a good ground so the current can travel through the device and give it power if you dont have a closed curcuit it could be called an open curcuit and the power would be off. The metal surface you attach the ground to is the chasis and you could think of the chasis as a large wire returning current back to youre altinator to keep youre battery charged and youre electronic components working. Andres is right about wanting the shortest length of wire for the ground but is wrong about the heat and current flow if you did run a ground all the way back to the negitive terminal it would do the same as grounding it to the chasis and as long as you used the proper gauge wire (AWG) there should be no heat and proper current flow, heat is caused by resistance and measured in ohms, current is mesured in amperes. I would definitly not suggest running the wire all the way back it would be a waste of supplies and cash but use the right size.