CBSE Class 12 Physics 2026 — QuizCluster Solutions
Comprehensive question-by-question independently authored solutions for CBSE Class 12 Physics Board Examination (2026). Questions are referenced directly to the official CBSE Question Paper.
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Q1 of 33Practice chapter-wise adaptive MCQs to strengthen weak concepts from this board paper.
View all years for this subjectElectric Flux through Closed Surface (Gauss's Law)
Step 1: Total flux by Gauss's Law
According to Gauss's Theorem, total electric flux enclosed by a closed symmetrical surface is Φ_total = q_enclosed / ε₀ = q / ε₀.
Step 2: Flux through a single face
A cube has 6 identical symmetrical faces. Due to spherical symmetry of the central charge, flux is equally divided among all 6 faces: Φ_face = Φ_total / 6 = q / (6ε₀).
- Gauss's Law: ∮ E · dA = q_enclosed / ε₀
- Symmetrical face flux: Φ_face = q / (6ε₀)
Flux through each face is independent of the side length L of the cube as long as the charge remains centered inside.
Confusing total cube flux (q/ε₀) with single face flux (q/6ε₀).
Source of question paper: Central Board of Secondary Education (CBSE). QuizCluster provides independently prepared educational solutions and explanations. QuizCluster is an independent educational platform and is not affiliated with or endorsed by CBSE. Question papers are accessed through links to official CBSE resources and are not hosted by QuizCluster.