A : In a material medium the speed of a particle can be more than the speed of light in that medium.
R : In the phenomenon of green house effect, low wavelength radiation is allowed to pass but high wavelength radiation is not allowed to pass.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the given question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states: "In a material medium, the speed of a particle can be more than the speed of light in that medium."

- In physics, the speed of light in a medium is given by the formula \( v = \frac{c}{\mu} \), where \( c \) is the speed of light in a vacuum and \( \mu \) is the refractive index of the medium.
- The assertion suggests that particles can travel faster than this speed. This is indeed possible for certain particles, such as charged particles moving through a medium, which can exceed the speed of light in that medium. This phenomenon is known as Cherenkov radiation.

**Conclusion for Assertion (A):** The assertion is correct.

### Step 2: Analyze the Reason (R)
The reason states: "In the phenomenon of greenhouse effect, low wavelength radiation is allowed to pass but high wavelength radiation is not allowed to pass."

- The greenhouse effect involves the trapping of heat in the Earth's atmosphere. Shorter wavelengths (like visible light) can pass through the atmosphere and reach the Earth's surface, while longer wavelengths (like infrared radiation) are absorbed and re-emitted by greenhouse gases, preventing them from escaping back into space.
- This means that the reason accurately describes the greenhouse effect.

**Conclusion for Reason (R):** The reason is also correct.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to determine if the reason explains the assertion.

- The assertion talks about the speed of particles in a medium, while the reason discusses the greenhouse effect and the behavior of radiation wavelengths.
- Although both statements are correct, they address different concepts and do not explain each other.

### Final Conclusion
Both the assertion and the reason are correct, but the reason does not explain the assertion.

**Answer:** Option 2 (Assertion is correct, Reason is correct, but Reason does not explain Assertion)

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