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3. current electricity — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics3. current electricity1 Mark
MCQ
The voltage $V$ and current $I$ graph for a conductor at two different temperatures ${T_1}$ and ${T_2}$ are shown in the figure. The relation between ${T_1}$ and ${T_2}$ is
  • ✓
    ${T_1} > {T_2}$
  • B
    ${T_1} \approx {T_2}$
  • C
    ${T_1} = {T_2}$
  • D
    ${T_1} < {T_2}$
✓

Answer

Correct option: A.
${T_1} > {T_2}$
a
Slope of the $V-i$ curve at any point equal to resistance at that point. From the curve slope for $T_1$ > slope for $T_2$

$ \Rightarrow $ ${R_{{T_1}}} > {R_{{T_2}}}$. Also at higher temperature resistance will be higher so $T_1 > T_2$

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