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In a parallel plate capacitor, the area of each plate is A=1 m² and the distance between the two plates is d=1 mm. Then the capacitance of the capacitor is C= ______ F.

Asked in GSEB Board July 2021 · Capacitance of a conductor and a capacitor

Answer: (2) 8.85×10⁻⁹

Step-by-step solution

Given: A=1 m², d=1 mm=1×10⁻³ m, vacuum (air) between the plates.

Idea: C=(ε₀A)/d with ε₀=8.85×10⁻¹² F m⁻¹.

C=(8.85×10⁻¹²×1)/(1×10⁻³).

C=8.85×10⁻⁹ F, about 8.85 nF.

Even a square metre of plate a millimetre apart gives only nanofarads — which is why practical capacitors use thin dielectrics and rolled foils.

Why the other options are wrong

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