Question Detail
Question
The plates of a parallel plate air capacitor are charged to 100 V. A 2mm plate is inserted between the plates of the capacitor. To maintain the same potential difference, the distance between the capacitor plates is increased by 1.6mm. The dielectric constant of the plate is
Correct Answer
Option B is the correct answer.
Detailed Explanation
Using d_extra = t(1 - 1/K), where t = 2mm is the slab thickness and 1.6mm is the extra separation needed: 1.6 = 2(1 - 1/K), giving K = 5.
Hint
Use the formula for the shift in plate separation caused by inserting a dielectric slab: Δd = t(1 - 1/K).