Assertion : When a capacitor is charged by a battery. Half of the energy supplied by the battery is stored in the capacitor and rest half is lost.
Reason : If resistance in the circuit is zero, then there will be no loss of energy.

Options

A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that when a capacitor is charged by a battery, half of the energy supplied by the battery is stored in the capacitor, and the rest is lost.

- **Energy Supplied by the Battery**: The energy supplied by the battery when charging a capacitor can be calculated using the formula:
\[ W_{\text{battery}} = V \cdot Q \]
where \( V \) is the voltage of the battery and \( Q \) is the charge stored in the capacitor.

- **Energy Stored in the Capacitor**: The energy stored in a capacitor is given by:
\[ W_{\text{capacitor}} = \frac{1}{2} C V^2 \]
where \( C \) is the capacitance and \( V \) is the voltage across the capacitor.

- **Energy Loss**: The energy loss can be calculated as:
\[ W_{\text{loss}} = W_{\text{battery}} - W_{\text{capacitor}} = QV - \frac{1}{2} C V^2 \]
Since \( Q = C V \), substituting gives:
\[ W_{\text{loss}} = CV^2 - \frac{1}{2} C V^2 = \frac{1}{2} C V^2 \]
This shows that half of the energy supplied by the battery is indeed lost, confirming the assertion is true.

### Step 2: Understand the Reason
The reason states that if the resistance in the circuit is zero, then there will be no loss of energy.

- **Resistance and Energy Loss**: In an ideal circuit with zero resistance, the current can flow without any opposition. However, energy can still be lost due to the nature of charging a capacitor. The energy loss occurs due to the fact that the capacitor takes time to charge and during this time, energy is dissipated in the form of heat or electromagnetic radiation, even if resistance is zero.

### Conclusion
- **Assertion**: True (half of the energy is stored, half is lost).
- **Reason**: False (energy loss can still occur even if resistance is zero).

Thus, the correct answer is that the assertion is true and the reason is false.

### Final Answer
Assertion is true, and the reason is false.

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