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Question
If there were only one type of charge in the universe, then ______.
- `oint_s` E.dS ≠ 0 on any surface.
- `oint_s` E.dS = 0 if the charge is outside the surface.
- `oint_s` E.dS could not be defined.
- `oint_s` E.dS = `q/ε_0` if charges of magnitude q were inside the surface.
Options
a and d
a and c
b and d
c and d
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Solution
b and d
Explanation:
From Gauss’ law, we know `oint_s` E.dS = `q/ε_0`, here q is the charge enclosed by the closed surface. If `oint_s` E.dS = 0 then q = 0, i.e., net charge enclosed by the surface must be zero. If the charge is outside the surface, then charge enclosed by the surface is q = 0 and thus, `oint` E.dS = 0.
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