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Question
A closed surface in vacuum encloses charges –q and +3q. The total electric flux emerging out of the surface is :
Options
Zero
`(2q)/∈_0`
`(3q)/∈_0`
`(4q)/∈_0`
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Solution
`(2q)/∈_0`
`phi = q_(enc)/∈_0 = (+3q - q)/∈_0 = (2q)/∈_0`
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