Question 332: Electrostatics & Capacitance

Question

Determine the charge on the capacitor in the
following circuit :

Accepted Answer

Assuming
potential x and y at the top junctions A and B respectively and zero potential
at lower junctions.
At the junction A applying KCL,
i
1
+ i
2
+ i
3
= 0
$${{x - 72} \over 6} + {x \over 4} + {{x - y} \over 2} = 0$$
$$ \Rightarrow $$ $${{2x - 144 + 6x - 6y + 3x} \over {12}} = 0$$
$$ \Rightarrow $$ 11x - 6y = 144  ......(1)
At the junction B applying KCL,
i
4
+ i
5
= 0
$${{y - x} \over 2} + {y \over {10}} = 0$$
$$ \Rightarrow $$ $${{5y - 5x + y} \over {10}}$$ = 0
$$ \Rightarrow $$ 6y = 5x ......(2)
Solving (1) and (2)
11x - 5x = 144
$$ \Rightarrow $$ x = 24 V
$$ 	herefore $$ y = 20 V
The charge on the capacitor, q = CV
$$ \Rightarrow $$ q = 10$$\mu $$F ÃÂ 20 = 200 $$\mu $$C

Answer

200μC

Answer

2μC

Answer

10μC

Answer

60μC

Electrostatics & Capacitance

Determine the charge on the capacitor in the following circuit :

Choose the correct answer: