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Question
In the Figure below, the current-voltage graphs for a conductor are given at two different temperatures, T1 and T2.
- At which temperature T1 or T2 is the resistance higher?
- Which temperature (T1 or T2) is higher?
Solution
(a) For the I-V graph, the slope of the I-V graph gives the conductance
`R = "V"/"I" = 1/tanθ`
Since θ1 > θ2
tan θ1 > tan θ2
So Resistance at T1 < Resistance at T2
(b) Since the resistance of a conductor rises with temperature and ‘R’ at T2 is higher than ‘R’ at T1, so T2 > T1
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