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A parallel plate capacitor is maintained at a certain potentail difference. When a 3mm thick slab is intorduced between the plate, in a order to maintain the same potential difference, the distance between the plates is increased by 2.4 mm. Find the dielectric constant of the slab. |
Answer» Here, `t = 3mm, x = 2.4 mm, K = ?` With air as dielectric, `C_(0) = (in_(0) A)/(d)` If `d_(1)` is new distance of separation between the plates when dielectric is introduced, then `C_(0) = (in_(0) A)/(d_(1) - t (1- (1)/(K)))` As `C = C_(0)` , therefore , `d_(1) - t (1- (1)/(K)) = d` or `t (1 - (1)/(K)) = d_(1) - d = x` As t = 3mm and `x = d_(1) -d = 2.4 mm` `:. 3(1 - (1)/(K)) = 2.4` `1 - (1)/(K) = (2.4)/(3) = 0.8` `(1)/(K) = 1-0.8 = 0.2, K = ` |
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