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प्रश्न
A charge Q is placed at the centre of a cube. The electric flux through one of its faces is ______.
विकल्प
`Q/epsi_0`
`Q/(6epsi_0)`
`Q/(8epsi_0)`
`Q/(3epsi_0)`
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उत्तर
A charge Q is placed at the centre of a cube. The electric flux through one of its faces is `underlinebb(Q/(6epsi_0))`.
Explanation:
Assuming the cube as a Gaussian surface, the total flux passing through the cube of side l can be given as,
`phi = Q/epsi_0`
Flux through each face of the cube: As the charge is placed symmetrically to each face of the cube, thus electric flux passing through each face is equal.
∴ Electric flux passing through each face,
`phi^' = phi/6 = Q/(6epsi_0)`
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