Timeline for Direct current and metallic conduction
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 25, 2013 at 13:05 | comment | added | Rijul Gupta | Well charge shall not accumulate could be explained by saying that when electrons start passinv through smaller cross sectional area, they start leaving behind same amount of positive ions for a smaller area this results in an increased field which force the electrons to move faster through the region of lesser area. | |
| Oct 25, 2013 at 12:31 | comment | added | odg | I do understand that if we want a direct current no charge should accumulate. But the point in my question is why should it be constant? I'm trying to get a feeling of it, to understand the microscopic process itself. Why would charge move faster in a smaller cross sectional area? "Charge shall not accumulate" is not really an answer for my question. I'm curious about the cause itself of such a behavior of electrons. | |
| Oct 24, 2013 at 18:19 | comment | added | Rijul Gupta | Your assumption is wrong because at any time a given amount of charge has to pass through each and every portion of wire so that there is no accumulation of charge at any point of wire. When you increase the resistance for same length of wire yoh effectively decrease its cross sectional area, as same amount of charge has to pass through the now smaller area in same time so as to keep rate of flow constant it must flow at higher rate, you can even feel this high speed at high resistance portions of wire as they are heated more than the lower resistance portions. | |
| Oct 24, 2013 at 17:09 | comment | added | odg | But what if electron is moving through a conductor with almost no resistance? Say, moving though the wires until it encounters some resistor (with not so negligible resistance). They must then accelerate and gain a bigger velocity when they're moving through medium with negligible resistance. It seems reasonable for me to think that electrons are moving faster where the resistance is lower and slower where it is higher. So if we have zones with different resistances, electrons will move with different speed and thus the current will vary. | |
| Oct 23, 2013 at 1:55 | history | answered | Rijul Gupta | CC BY-SA 3.0 |