Electrostatics Question 806
Question: A parallel plate capacitor with air between the plates is charged to a potential difference of 500 V and then insulated. A plastic plate is inserted between the plates filling the whole gap. The potential difference between the plates now becomes 75V. The dielectric constant of plastic is
Options:
A) 10/3
B) 5
C) 20/3
D) 10
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ V _{0}=\frac{q}{C _{0}} $
$ V=\frac{q}{C}\Rightarrow \frac{V}{V _{0}}=\frac{C _{0}}{C}\Rightarrow \frac{C _{0}}{C}=\frac{500}{75}=\frac{20}{3} $
