Kirchhoff's current law is the law of conservation of

Options

A. charge
B. momentum
C. energy
D. current

Answer

### Step-by-Step Solution:

1. **Understanding Kirchhoff's Current Law (KCL)**:
- Kirchhoff's Current Law states that at any junction in an electrical circuit, the total current entering the junction must equal the total current leaving the junction.

2. **Mathematical Representation**:
- If we denote the currents entering the junction as \( I_1 \) and \( I_2 \), and the currents leaving the junction as \( I_3 \) and \( I_4 \), we can express this as:
\[ I_1 + I_2 = I_3 + I_4 \]
- This can also be rearranged to show that the algebraic sum of currents at the junction is zero:
\[ I_1 + I_2 - I_3 - I_4 = 0 \]

3. **Conservation Principle**:
- KCL is fundamentally based on the principle of conservation of charge. This means that the total charge in a closed system remains constant over time. Since current is defined as the rate of flow of charge, the total charge flowing into the junction per unit time must equal the total charge flowing out.

4. **Conclusion**:
- Therefore, Kirchhoff's Current Law is the law of conservation of charge.

### Final Answer:
Kirchhoff's Current Law is the law of conservation of **charge**.

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