Question

Capacitors $C_{1}(10 \,\mu F )$ and $C_{2}(20 \,\mu F )$ are connected in series across a $3 \,kV$ supply, as shown. What is the charge on the capacitor $C_{1}$ ?

• A. $45000\,\mu C$
• B. $20000\, \mu C$
• C. $15000 \,\mu C$
• D. $10000 \,\mu C$

Answer 1

Answer: (B)

$\frac{1}{C}=\frac{1}{10}+\frac{1}{20}=\frac{3}{20}$
$C=\frac{20}{3} \,\mu F$
$q=\frac{20}{3} . 3000$
$=20000 \times 10^{-6}$
$q=2 \times 10^{-4} \,C$