Dear sir you had got drift velocity to be less than one ...but as soon as we close the switch electrons start flowing without taking a unit second but if it would with the speed less than 1 how we will get current as soon as we close the switch???
9 years ago
by
Abinay gangireddygari
Ans
1
->
It is only the drift velocity which is less but the electron density is very very high.due to this reason even the small velocity of electrons can cause large values of currents..
8 years ago
by
L.m.rama krishna
Ans
2
->
are yaar this is a famous question. let me take a example, there are thousands of soldiers arranged in a queue(electrons in a conductor), and there is a water bottle(bulb) just in front of the first soldier.
the water empties(bulb glows) only when a soldier drinks it(electrons reach it).
so when they are commanded to march(battery on), the first soldier(first eletron) would take no time to reach the bottle(bulb), hence water is emptied(bulb glows) no matter if the speed of the soldiers is 1 mm/s.
8 years ago
by
Saurabh kumar nayak
Ans
3
->
The best explanation could be like if the drift velocity has a magnitude in 10^-4 m/s, then how does a bulb glows almost instantly when the switch turns on.
This is due to the fact that electrons are present in the whole wire,and also inside the bulb,where current has to be supplied. As soon as an electric field is set up,all the electrons move with a drift velocity.So,the bulb glows almost instantly.
8 years ago
by
Shivam Agarwal