Ohm's Law

What is Ohm’s Law?
An Introduction to Ohms, Amps, and Volts

Have you heard of Ohm’s Law, but never really understood what it means? Do you know why different electronics require more or less voltage? Does that always mean it will use more electricity? 

Ohm’s Law in basic terms: The electrical current (measured in amps) you can transfer through any wire is proportional to the voltage, and inversely proportional to the resistance, of the wire (measured in Ohms). So as you increase voltage, the current is greater, but as you add resistance, you get less current. That means as the wire gets longer, you are adding resistance, so you use more voltage to keep the current up to the amps you need.