Temperature coefficient of resistance

Discussion in 'Physics' started by logearav, Jan 24, 2012.

  1. logearav

    Thread Starter Member

    Aug 19, 2011
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    The formula for temperature coefficient of resistance is
    \alpha = ΔR/R0 ΔT
    where R is R - R0, where R0 is the resistance at reference temperature usually at 0°C or 20°C.
    ΔT is T - T0, again T is 0° or 20°C
    when written explicitly we get
    \alpha = (R - R0)/R0 (T - T0)
    But while measuring temperature coefficient of resistance of the material of the coil, in metre bridge experiment,
    we use the relation \alpha = R2 - R1/(R1t2 -R2t1).
    How R1 and R2 comes in this relation, whereas in the original formula there is only R0.
     
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  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    3,782
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    There is no difference other than the choice of variable names.
     
  3. MrChips

    Moderator

    Oct 2, 2009
    12,436
    3,360
    It appears that you are using equations from two different sources.
    Just substitute R = R2, R0 = R1. Also T = t2, T0 = t1.
     
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