A : An electron has negative charge by definition
R : Charge of a body depends on its velocity.

Options

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

**Assertion (A): An electron has negative charge by definition.**
1. By definition, an electron is a fundamental particle that carries a negative electric charge. This is a well-established fact in physics.
2. Therefore, the assertion is **true**.

**Reason (R): Charge of a body depends on its velocity.**
1. The charge of a body is a property that does not change with its velocity. Charge is an intrinsic property of particles and is independent of their motion.
2. Therefore, the reason is **false**.

**Conclusion:**
- Since the assertion is true and the reason is false, the correct answer is that the assertion is true but the reason is false.

Thus, the correct option is **C**: Assertion is true, but the reason is false.

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