Current Values
1. **State the problem:** We have a parallel circuit with four branches involving currents $i_A$, $i_B$, and $i_C$, voltage $V_x$ across an 18 \(\Omega\) resistor, and given currents and resistances. We need to find $i_A$, $i_B$, and $i_C$.
2. **Identify values and relations:**
- Current source in first branch: $5.6\ A$
- Second branch: resistor $R_2=18\ \Omega$, voltage across it $V_x$, current $i_A$
- Third branch: current-controlled current source (CCCS) $i_B=0.1 V_x$
- Fourth branch: resistor $R_4=9\ \Omega$ with current $i_C$, then a $2\ A$ current source
3. **Write equations for currents in branches:**
All four branches are in parallel, so voltage across each branch is the same and equal to $V_x$.
- For the second branch: $i_A = \frac{V_x}{R_2} = \frac{V_x}{18}$
- For the third branch: $i_B = 0.1 V_x$
- For the fourth branch: two elements in series, current source of 2 A sets $i_C = 2\ A$
4. **Apply Kirchhoff's Current Law (KCL) at the node:**
Sum of currents into node equals sum out.
Assuming currents downward are positive, total current from node = sum of branch currents:
$$ 5.6 = i_A + i_B + i_C $$
Substitute known expressions:
$$ 5.6 = \frac{V_x}{18} + 0.1 V_x + 2 $$
5. **Solve for $V_x$: **
$$ 5.6 - 2 = \frac{V_x}{18} + 0.1 V_x $$
$$ 3.6 = \frac{V_x}{18} + 0.1 V_x = \frac{V_x}{18} + \frac{0.1\times 18 V_x}{18} = \frac{V_x + 1.8 V_x}{18} = \frac{2.8 V_x}{18} $$
$$ 3.6 = \frac{2.8 V_x}{18} \implies V_x = \frac{3.6 \times 18}{2.8} = \frac{64.8}{2.8} = 23.1429\ V $$
6. **Calculate currents $i_A$, $i_B$, $i_C$ using $V_x$: **
- $i_A = \frac{V_x}{18} = \frac{23.1429}{18} = 1.2857\ A$
- $i_B = 0.1 V_x = 0.1 \times 23.1429 = 2.3143\ A$
- $i_C = 2\ A$ (given)
7. **Final answer:**
$$ i_A \approx 1.29\ A $$
$$ i_B \approx 2.31\ A $$
$$ i_C = 2.00\ A $$