Question

Using Kirchhoff’s law, find the current flowing through the given circuit.

• A. \( 7.5 \, \text{A} \)
• B. \( 5 \, \text{A} \)
• C. \( 10 \, \text{A} \)
• D. \( 3 \, \text{A} \)

Hint:

Always check the polarity of cells carefully before adding or subtracting emfs.

Answer 1

The Correct Option is B

Step 1: Identify components of the circuit.
The circuit contains two cells of emf \( 200\,\text{V} \) and \( 10\,\text{V} \) connected in opposition and a resistor of \( 38\,\Omega \).
Step 2: Find net emf.
Since the cells oppose each other, \[ E_{\text{net}} = 200 - 10 = 190 \, \text{V} \]
Step 3: Apply Kirchhoff’s loop law.
\[ E_{\text{net}} = IR \]
Step 4: Calculate current.
\[ I = \frac{190}{38} = 5 \, \text{A} \]
Step 5: Conclusion.
The current flowing through the circuit is \( 5 \, \text{A} \).