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Physics · PYQ NEET UG 2025
हिन्दीThe plates of a parallel plate capacitor are separated by \( d \). Two slabs of different dielectric constant \( K_1 \) and \( K_2 \) with thickness \( \frac{3}{8}d \) and \( \frac{d}{2} \) respectively are inserted in the capacitor. Due to this, the capacitance becomes two times larger than when there is nothing between the plates. If \( K_1 = 1.25 K_2 \), the value of \( K_1 \) is:
Correct answer · Option 1
2.66
Explanation
Effective distance \( d_{eff} = d - t_1 - t_2 + \frac{t_1}{K_1} + \frac{t_2}{K_2} \). Given \( C' = 2C \implies d_{eff} = d/2 \). Substituting \( t_1 = \frac{3}{8}d, t_2 = \frac{d}{2} \) and \( K_1 = 1.25 K_2 \) yields \( K_1 = 2.66 \).
