If a point charge q is placed at the centre of a cube, what is the flux linked with each face of cube?
Correct answer: D. Φ/6
- A. Φ
- B. 0
- C. Φ/3
- D. Φ/6
Explanation
According to Gauss's Law, the total electric flux Φ through a closed surface is equal to the charge enclosed q divided by the permittivity of free space ε0 (Φ = q/ε0). When a point charge q is placed at the center of a cube, the cube is a symmetrical shape, and the flux is distributed equally among the six faces. Therefore, the flux through each face is Φ/6 = q/(6ε0). Other options are incorrect because they either misapply Gauss's Law or misunderstand the symmetry and distribution of electric flux.
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