A: Superconducting magnets are gainfully exploited in running magnetically levitated superfast trains.
R: Superconductors are diamagnetic substances which get repelled by strong external magnetic field.

Options

A. If both Assertion & Reason are the true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reson 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 assertion and reason question, we will analyze both statements step by step.

### Step 1: Understanding the Assertion
The assertion states that "Superconducting magnets are gainfully exploited in running magnetically levitated superfast trains."

**Explanation:**
- Superconducting magnets are used in maglev (magnetically levitated) trains to enable them to float above the tracks. This is because superconductors exhibit a phenomenon called perfect diamagnetism, which allows them to repel magnetic fields.

### Step 2: Understanding the Reason
The reason states that "Superconductors are diamagnetic substances which get repelled by strong external magnetic fields."

**Explanation:**
- Superconductors, when cooled below a certain critical temperature, exhibit perfect diamagnetism. This means that they will completely expel any magnetic field from their interior (Meissner effect). When an external magnetic field is applied, the superconductor generates an opposing magnetic field, leading to repulsion.

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

- The assertion is true because superconducting magnets are indeed used in maglev trains.
- The reason is also true because superconductors are diamagnetic and repel external magnetic fields, which is the principle that allows maglev trains to levitate.

### Conclusion
Both the assertion and the reason are true, and the reason provides a correct explanation for the assertion.

### Final Answer:
- **Assertion (A)**: True
- **Reason (R)**: True
- **Conclusion**: R is the correct explanation of A.

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