A: Gravitational force is always attractive but electromagnetic force can be attractive or repulsive:
R : Mass comes only in one variety (there is no negative mass) but charge comes in two varieties. (Positive and negative charge)

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 analyze the statements A and R, we can break down the solution into the following steps:

### Step 1: Analyze Statement A
- **Statement A**: "Gravitational force is always attractive but electromagnetic force can be attractive or repulsive."
- The gravitational force acts between two masses and is always attractive. This is a fundamental property of gravity, as it pulls masses towards each other.
- The electromagnetic force, on the other hand, can be either attractive or repulsive depending on the types of charges involved (like charges repel, unlike charges attract).

**Conclusion for Step 1**: Statement A is correct.

### Step 2: Analyze Statement R
- **Statement R**: "Mass comes only in one variety (there is no negative mass) but charge comes in two varieties (positive and negative charge)."
- Mass is a scalar quantity and is always positive; there is no concept of negative mass in classical physics.
- Charge, however, can be of two types: positive and negative. This duality allows for both attractive and repulsive interactions in electromagnetic forces.

**Conclusion for Step 2**: Statement R is also correct.

### Step 3: Determine the Relationship Between A and R
- We need to establish if Statement R provides a correct explanation for Statement A.
- Since Statement R explains why gravitational force is always attractive (mass is always positive) and why electromagnetic force can be both attractive and repulsive (due to the existence of positive and negative charges), it serves as a valid explanation for Statement A.

**Conclusion for Step 3**: Statement R is a correct explanation of Statement A.

### Final Conclusion
Both statements A and R are correct, and R correctly explains A.

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