THE “ELECTRICITY” INSIDE OF WIRES MOVES AT THE SPEED OF LIGHT?
November 15, 2010 Leave a comment
Wrong. In metals, electric current is a flow of electrons. Many books claim that these electrons flow at the speed of light. This is incorrect. Electrons actually flow quite slowly, at speeds on the order of centimeters per minute. It’s the energy in the circuit which flows fast, not the electrons. When the electrons at one point in the circuit are pumped, electrons in the entire loop of the circuit are forced to flow, and energy spreads almost instantly throughout the entire circuit. This happens even though the electrons move very slowly. To aid your understanding, imagine a large wheel. If you give it a spin, the entire wheel moves as a unit, and this is how you transmit mechanical energy almost instantly to all parts of the wheel’s rim. But the wheel itself didn’t move very fast. The material of the wheel is like the electrons in a wire. Electrical energy is like the “jerk,” the mechanical energy wave which you sent to all parts of the wheel when you gave it a spin. Mechanical energy moves incredibly quickly to all parts of the wheel, but the wheel’s atoms didn’t have to rapidly travel anywhere in order for this to happen.