Two thin dielectric slabs of dielectric constants K1&K2 () are inserted between plates of a parallel capacitor, as shown in the figure. The variation of electric field E between the plates with distance d as measured from plate P is correctly shown by:
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A parallel plate capacitor is made of two dielectric blocks in series. One of the blocks has thickness d1 and dielectric constant K1 and the other has thickness d2 and dielectric constant K2, as shown in the figure. This arrangement can be thought of as a dielectric slab of thickness d = d1 + d2 and effective dielectric constant K. K is:
1. | \(\frac{\mathrm{K}_{1} \mathrm{~d}_{1}+\mathrm{K}_{2} \mathrm{~d}_{2}}{\mathrm{~d}_{1}+\mathrm{d}_{1}}\) | 2. | \(\frac{\mathrm{K}_{1} \mathrm{~d}_{1}+\mathrm{K}_{2} \mathrm{~d}_{2}}{\mathrm{~K}_{1}+\mathrm{K}_{2}}\) |
3. | \(\frac{\mathrm{K}_{1} \mathrm{~K}_{2}\left(\mathrm{~d}_{1}+\mathrm{d}_{2}\right)}{\mathrm{K}_{1} \mathrm{~d}_{2}+\mathrm{K}_{2} \mathrm{~d}_{1}}\) | 4. | \(\frac{2 \mathrm{~K}_{1} \mathrm{~K}_{2}}{\mathrm{~K}_{1}+\mathrm{K}_{2}}\) |