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3. current electricity — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics3. current electricity1 Mark
MCQ
The length of the wire is doubled. Its conductance will be
  • A
    Unchanged
  • ✓
    Halved
  • C
    Quadrupled
  • D
    $1/4$ of the original value
✓

Answer

Correct option: B.
Halved
b
(b) Conductance $C = \frac{1}{R} = \frac{A}{{\rho l}}\, \Rightarrow \,C \propto \frac{1}{l}$

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