Assertion : A hollow metallic closed container maintained at a uniform temperature cab act as a source of black body radiation.
Reason : All metals act as a black body.

Options

A. If both the Asseration and Reason are true and reason explains the Assertion :
B. If both the Assertion and Reason are true but reason does ot explain the Assertion :
C. If Assertion is true but reason 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 "A hollow metallic closed container maintained at a uniform temperature can act as a source of black body radiation."
- A black body is defined as an idealized physical object that absorbs all incoming radiation and re-emits it perfectly at a given temperature. A hollow container at uniform temperature can indeed emit thermal radiation similar to that of a black body, as it absorbs all incoming radiation and re-emits it.

**Step 2: Analyze the Reason**
- The reason states that "All metals act as a black body."
- This statement is incorrect. While some metals can absorb and emit radiation, they do not behave as perfect black bodies. Most metals reflect a significant amount of incoming radiation and do not absorb all wavelengths of light, which is a characteristic of a black body.

**Step 3: Conclusion**
- Since the assertion is true (the hollow metallic container can act as a black body), but the reason is false (not all metals act as black bodies), we conclude that the correct answer is:
- Assertion is true, but the reason is false.

**Final Answer:**
- Option C: Assertion is true, but reason is false.

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