I'll be more specific to avoid confusion. When I flip the light switch, how long before the light comes on? I know that electricity doesn't really move, it just vibrates, but you know what I'm saying. Speed of light in vaccuum, right?
2007-06-23 06:16:57 · 5 answers · asked by Ryan K 2 in Science & Mathematics ➔ Physics
Electrons traveling through a vacuum typically travel at speeds around 1/10 the speed of light. In a wire, however, an electron experiences numerous collisions, and therefore its speed, or more properly, drift velocity, is on the order of 1 foot per hour. When you flow water through a garden hose, it also takes time for water to pass through. Yet when the hose is filled with water, it seems like the water moves through instantaneously. In reality, because water is fairly incompressible, one packet of water pushes against the next packet, until eventually the packet near the end of the hose is pushed out. The same thing is true of current in a wire, except that the electric field, which travels at the speed of light, is responsible for pushing the electrons out at the other end.
2007-06-23 12:06:23 · answer #1 · answered by Jeff 3 · 0⤊ 0⤋
In wires, electrons do move. Electron currents do flow across the wires (usually in a back and forth motion with AC current at 60 cycles per second). But it's not light-speed. They accelerate fast, being so light, but can't accelerate forever. They often bump into a cloud of electrons that deflects or stops them so they are stopping and starting. The average speed can be 10%-50% of the speed of light or something. This is a problem in computers. The smaller you make microchip circuits, the more the electrons have to "turn corners" and they slow down. Weird quantum effects start to happen like "electron tunnelling". You don't expect electrons to jump an insulator gap -- but sometimes they do!
2007-06-23 06:58:21 · answer #2 · answered by PIERRE S 4 · 1⤊ 0⤋
The electrons in a wire move very slowly. centimeters per minute.
But the electric current that gets passed down the wire moves at the speed of light.
2007-06-23 06:27:31 · answer #3 · answered by Anonymous · 0⤊ 1⤋
depends on the medium. with your light switch probably about 60% the speed of light
2007-06-23 06:27:01 · answer #4 · answered by alex 3 · 1⤊ 1⤋
The speed is real real quick!
2007-06-23 06:21:57 · answer #5 · answered by Vergie 3 · 0⤊ 0⤋