(A) : If two beams of protons move parallel to each other in same direction then these beams repel each other.
(R) : Like charges repel while opposite charges attract each other.

Options

A. Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.
B. Both 'A' and 'R' are true and 'R' is not the correct explanation of 'A'
C. 'A' is true and 'R' is false
D. 'A' is false and 'R' is false

Answer

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that if two beams of protons move parallel to each other in the same direction, then these beams repel each other.
- Protons are positively charged particles, and according to electrostatic principles, like charges repel each other.

2. **Understanding the Reason**:
- The reason provided states that like charges repel while opposite charges attract each other.
- This is a fundamental principle of electrostatics and is indeed true.

3. **Analyzing the Interaction Between the Beams**:
- When two beams of protons (which are positively charged) move parallel to each other, they create magnetic fields around them due to their motion.
- However, the electrostatic force (which is responsible for the repulsion of like charges) is stronger than the magnetic force in this scenario.
- Therefore, the assertion that the beams repel each other is correct.

4. **Evaluating the Relationship Between Assertion and Reason**:
- While both the assertion and the reason are true, the reason does not provide a direct explanation for the assertion.
- The assertion is based on the electrostatic repulsion of like charges, while the reason discusses the general principle of like charges repelling each other without addressing the specific scenario of moving beams.

5. **Conclusion**:
- Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
- Therefore, the final answer is that both A and R are true, but R is not the correct explanation of A.

### Final Answer:
Both A and R are true, but R is not the correct explanation of A.

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