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Questions
Define electric flux.
Define electric flux. Is it a scalar or a vector quantity?
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Solution 1
Electric flux is the total number of lines of force passing through the unit area of a surface held perpendicularly.
Electric flux ΔΦ through an area element ΔS is given by
ΔΦ = E.ΔS = EΔScosθ
θ is the angle between E and ΔS.
Solution 2
Electric flux is defined as the number of electric field lines crossing the per unit area. It is given as
`triangle phi = vecE.vec(triangleS) cos theta`
where `vecE` is Electric field and `vec(triangleS)`is area vector. The angle θ here is the angle between `vecE` and `vec(triangle S)`.
Since Electric flux is the dot product of two vectors, Hence it is a Scalar quantity.
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| (i) | (ii) | (iii) | (iv) |
A charge Qµc is placed at the centre of a cube the flux coming from any surface will be.




