In the following circuit, the magnitude of current I 1 , is ______ A .

Question

TestHub · Accepted Answer

The figure above shows the current and voltage at different points in circuit.

Applying Kirchhoff's Junction law at $A$ ,

$\frac{x - (y + 5)}{1} + \frac{x - 2}{2} + \frac{x - 0}{2} = 0 . . . (1)$

Applying Kirchhoff's Junction law at $B$ ,

$\frac{y + 5 - x}{1} + \frac{y - 0}{1} + \frac{y - 2}{1} = 0 . . . (2)$

Solving equation (1) and (2), we get

$x = 3$ and $y = 0$

Now, at $D$ junction

$I_{1} = i_{1} + i_{2}$

$\Rightarrow I_{1} = \frac{y - 0}{1} + \frac{x - 0}{2}$

$= \frac{0 - 0}{1} + \frac{3 - 0}{2}$

$\Rightarrow I_{1} = 1.5 A$ .

Physics - Current Electricity Question with Solution | TestHub