Electrostatics Question 78
Question: The area of the plates of a parallel plate condenser is $ A $ and the distance between the plates is $ 10mm $ . There are two dielectric sheets in it, one of dielectric constant 10 and thickness $ 6mm $ and the other of dielectric constant 5 and thickness $ 4mm $ . The capacity of the condenser is [MP PMT 1997]
Options:
A) $ \frac{12}{35}{\varepsilon _{0}}A $
B) $ \frac{2}{3}{\varepsilon _{0}}A $
C) $ \frac{5000}{7}{\varepsilon _{0}}A $
D) $ 1500\ {\varepsilon _{0}}A $
Show Answer
Answer:
Correct Answer: C
Solution:
$ C=\frac{{\varepsilon _{0}}A}{( \frac{t _{1}}{k _{1}}+\frac{t _{2}}{k _{2}} )}=\frac{{\varepsilon _{0}}A}{\frac{6\times {{10}^{-3}}}{10}+\frac{4\times {{10}^{-3}}}{5}}=\frac{5000}{7}{\varepsilon _{0}}A $
