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Electric flux, ϕ = EA cos θ, where θ = angle between E and normal to the surface. Here θ = π/2. Find ϕ.

1. ϕ = q / ε₀
2. ϕ = 0
3. ϕ = EA
4. ϕ = q / 2ε₀

Correct answer: ϕ = 0

Solution

The electric flux is given by ϕ = EA cos θ. When θ = π/2, cos(π/2) = 0, so ϕ = 0.

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