How does electricity travel so quickly?

[sambarbarian]

HI! i only know about the basics of current and electricity , but, i wanted to ask this..

the drift velocity in electrons is approx 10^-4 and thermal velocity is 10^6 m/s , which is not very large compared to the length of wires connecting power stations and homes , but still we get electricity within seconds ... how can this be ?

 

[sophiecentaur]

The best arm waving answer I can think of is to liken the electrons to links in a chain. The energy gets from one end of the chain to the other as soon as you apply the force - the only delay being due to the speed that the links can pass on the tension from one to another (the speed of the wave / tension pulse along the chain). The links move at a few cm per second.

In the case of electrical power transfer, the wave carrying the energy moves at just a little short of the speed of light.

And you get 'the electricity', not in "seconds" but in microseconds