all in series
all in parallel
two in parallel and third in series with this combination
two in series and third in parallel across this combination
Answer is Right!
Answer is Wrong!
The correct answer is C. two in parallel and third in series with this combination.
The equivalent capacitance of two capacitors in parallel is the sum of their individual capacitances. The equivalent capacitance of two capacitors in series is the product of their individual capacitances divided by their sum.
If we have three capacitors each of the capacity $C$, we can connect them in the following ways:
- All in series: The equivalent capacitance of three capacitors in series is $C/3$.
- All in parallel: The equivalent capacitance of three capacitors in parallel is $3C$.
- Two in parallel and third in series with this combination: The equivalent capacitance of two capacitors in parallel is $2C$. The equivalent capacitance of this combination and the third capacitor in series is $2C + C = 3C$.
Therefore, the only way to obtain a resultant capacitance of $2/3C$ is to connect two capacitors in parallel and the third capacitor in series with this combination.