Question

A parallel plate capacitor with air as medium between the plates has a capacitance of `10 muF`. The area of capacitor is divided into two equal halves and filled with two media as shown in the figure having dielectric constnt `k_(1) = 2` and `k_(2) = 4`. the capacitance of the system will now be

A. `10 muF`
B. `20 muF`
C. `30 muF`
D. `40 muF`

Answer 1

Correct Answer - C
`C_(R ) = C_(1) + C_(2) = (k_(1) epsilon_(0) A_(1))/(d) + (k_(2)epsilon_(0)A_(2))/(d)`
`= (2 xx epsilon_(0) (A)/(2))/(d) + (4 xx epsilon_(0) (A)/(2))/(d) = 2 xx (10)/(2) + 4 xx (10)/(2) = 30 muF`