Question

Two equal capacitors are first connected in series and then in parallel. The ratio of the equivalent capacities in the two cases will be:

• A. 4:01
• B. 2:01
• C. 1:04
• D. 1:02

Answer 1

Answer: (C)

1:04

Answer 2

For series combination

$\frac{1}{C_{eq_1}} = \frac{1}{C} + \frac{1}{C}$
$\Rightarrow C_{eq_1} = \frac{C}{2}$
For parallel combination

$C_{eq_2} = C + C$
$\Rightarrow C_{eq_2} = 2C$
$\Rightarrow \frac{C_{eq_1}}{eq_2} =\frac{C/2}{2C}= \frac{1}{4} = 1 : 4$