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Question
A positive point charge Q is brought near an isolated metal cube.
Options
The cube becomes negatively charged.
The cube becomes positively charged.
The interior becomes positively charged and the surface becomes negatively charged.
The interior remains charge free and the surface gets non-uniform charge distribution.
Solution
The interior remains charge free and the surface gets non-uniform charge distribution.
Since the cube is metallic, the charge gets distributed on the surface and the interior remains charge-free. However, when a positive point charge Q is brought near the metallic cube, a negative charge gets induced on the face near the positive charge Q and an equal positive charge gets induced on the face, which is away from the charge Q. Thus, the metallic surface gets non-uniform charge distribution.
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