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Tungsten Filament & Ohm's Law.

  • 04-11-2012 07:36PM
    #1
    NegativeCreep
    Closed Accounts Posts: 4,351 ✭✭✭


    Can anyone provide me with a physical explanation as to why a tungsten filaments resistance increases with higher voltage?

    Also, why does it not obey Ohm's Law?


Comments

  • #2
    krd
    Banned (with Prison Access) Posts: 3,449 ✭✭✭krd


    NegativeCreep wrote: »
    Can anyone provide me with a physical explanation as to why a tungsten filaments resistance increases with higher voltage?

    Also, why does it not obey Ohm's Law?

    It's really higher temperature, that higher voltage. The hotter a conductor, the less well it conducts. The resistance increases. It doesn't break Ohm's law, because if you let the temperature stabilise the resistance stabilises too.


  • #3
    NegativeCreep
    Closed Accounts Posts: 4,351 ✭✭✭NegativeCreep


    krd wrote: »
    It's really higher temperature, that higher voltage. The hotter a conductor, the less well it conducts. The resistance increases. It doesn't break Ohm's law, because if you let the temperature stabilise the resistance stabilises too.

    Ah thanks dude :D Would've been fucked for college tomorrow without that answer!


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