2017 · Q29
A parallel-plate capacitor of capacitance C₁ is made using two gold plates. Another parallel-plate capacitor of capacitance C₂ is made using two aluminium plates with same plate separation, and all the four plates are of same area. If ρg and ρa are respectively the electrical resistivities of gold and aluminium, then which one of the following relations is correct?
General KnowledgePhysics
- AC₁ > C₂
- BC₂ > C₁
- CC₁ρa = C₂ρg
- DC₁ = C₂
Explanation
Capacitance C = ε₀A/d depends only on plate area, separation, and the intervening medium — not on the plate metal's resistivity. With identical geometry, C₁ = C₂; ρg and ρa are irrelevant distractors. Hence D.