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Physics · Electrostatic Potential
हिन्दीIn a parallel-plate capacitor, the electric field between plates is \( E_0 \). If a conducting slab of thickness \( t = \frac{d}{2} \) (where \( d \) is plate separation) is inserted between the plates without touching them, the ratio of new capacitance to initial capacitance is:
Correct answer · Option 3
\( 2 : 1 \)
Explanation
For a conducting slab, \( K = \infty \), so \( C = \frac{\varepsilon_0 A}{d - t} = \frac{\varepsilon_0 A}{d - d/2} = \frac{2\varepsilon_0 A}{d} = 2C_0 \). The ratio \( C / C_0 = 2 : 1 \).
