A : Different electromagnetic waves differ considerably in their mode of interaction with matter.
R : Different electromagnetic waves have different wavelength or frequency.

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

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "different electromagnetic waves differ considerably in their mode of interaction with matter."
- This is true because electromagnetic (EM) waves, such as radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays, interact with matter in various ways. For example, X-rays can penetrate soft tissues but are absorbed by denser materials like bones.

2. **Understanding the Reason (R)**:
- The reason states that "different electromagnetic waves have different wavelength or frequency."
- This is also true. The electromagnetic spectrum is characterized by waves of different wavelengths and frequencies. For instance, radio waves have long wavelengths and low frequencies, while gamma rays have very short wavelengths and high frequencies.

3. **Connecting Assertion and Reason**:
- The assertion (A) is correct, and the reason (R) explains why the assertion is true. The different wavelengths and frequencies of EM waves lead to different energies, which in turn affect how these waves interact with matter.
- For example, the high energy of gamma rays allows them to penetrate materials more effectively than lower-energy radio waves.

4. **Conclusion**:
- Both the assertion and the reason are correct, and the reason correctly explains the assertion.

### Final Answer:
- Assertion (A) is true.
- Reason (R) is true.
- The reason (R) correctly explains the assertion (A).

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