Question

When the switch $\text{S}$, in the circuit shown, is closed then the value of current $i$ will be:

• A. $4\text{A}$
• B. $3\text{A}$
• C. $2\text{A}$
• D. $5\text{A}$

Answer 1

The correct option is D $5\text{A}$


Let the voltage at $C=x\text{V}$

From Kirchhoff's current law,

$i_1+i_2=i$

$\Rightarrow \frac{20-x}{2}+\frac{10-x}{4}=\frac{x-0}{2}$

$\Rightarrow x=10$

$\therefore i=\frac{V}{R}=\frac{x}{R}=\frac{10}{2}=5\text{A}$

Hence, option $\left(B\right)$ is correct.