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STD 12 - 2. Electric potential and capacitance — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 - 2. Electric potential and capacitance4 Marks
MCQ
An empty thick conducting shell of inner radius $a$ and outer radius $b$ is shown in figure.If it is observed that the inner face of the shell carries a uniform charge density $-\sigma$ and the surface carries a uniform charge density $ '\sigma '$

If a point charge $q_A$ is placed at the center of the shell, then choose the correct statement $(s)$

  • A
    The charge must be positive
  • B
    The charge must be negative
  • C
    The magnitude of charge must be $4\ \pi \sigma a^2$
  • ✓
    $A$ and $C$ both
✓

Answer

Correct option: D.
$A$ and $C$ both
d

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