Question

Two charges of magnitudes – 2Q and + Q are located at points (a, 0) and (4a, 0) respectively. What is the electric flux due to these charges through a sphere of radius ‘3a’ with its centre at the origin? [CBSE (AI) 2013]

January 13, 2024

Answer

Electric flux, ϕ = $-{2Q\over \varepsilon_0 }$

Concept: Imagine a sphere of radius 3a about the origin and observe that only charge –2Q is inside the sphere.

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