Q. A parallel plate capacitor with air as medium between the plates has a capacitance of $10\mu F.$ The area of capacitor of divided into two equal halves and filled with two media as shown in the figure having dielectric constant $k_{1} = 2$ and $k_{2} = 4.$ The capacitance of the system will now be
A) $10\mu F$
B) $20\mu F$
C) $30\mu F$
D) $40\mu F$
Explanation
(c) $C_{R} = C_{1} + C_{2} = \frac{{k_{1}\varepsilon}_{0}A_{1}}{d} + \frac{k_{2}\varepsilon_{0}A_{2}}{d}$
$= \frac{2 \times \varepsilon_{0}\frac{A}{2}}{d} + \frac{4 \times \varepsilon_{0}\frac{A}{2}}{d} = 2 \times \frac{10}{2} + 4 \times \frac{10}{2} = 30\mu F$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.