(A) : The microscopic roots of magnetism can be traced back to intrinsic spin of electrons.
(R) : The spinning electron is equivalent to a magnetic dipole.

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 (A) and the reason (R) provided.

### Step 1: Understanding the Assertion (A)
The assertion states that "The microscopic roots of magnetism can be traced back to intrinsic spin of electrons."

- **Explanation**: This means that at a fundamental level, the phenomenon of magnetism arises from the behavior of electrons, particularly their intrinsic property known as spin. Spin is a quantum property of electrons that contributes to their magnetic characteristics.

### Step 2: Understanding the Reason (R)
The reason states that "The spinning electron is equivalent to a magnetic dipole."

- **Explanation**: A magnetic dipole is a magnetic entity that has a north and south pole. When an electron spins, it creates a magnetic field similar to that of a tiny bar magnet. This is because the spinning motion of the electron generates a magnetic moment, which is a vector quantity that represents the strength and direction of the magnetic field produced by the electron.

### Step 3: Establishing the Relationship between A and R
Now we need to determine if R correctly explains A.

- **Analysis**: The assertion A is true because the intrinsic spin of electrons is indeed a fundamental source of magnetism. The reason R is also true because it accurately describes how the spin of an electron behaves like a magnetic dipole. Therefore, R provides a correct explanation for A.

### Conclusion
Both the assertion (A) and the reason (R) are true, and R is the correct explanation of A.

### Final Answer
Both A and R are true, and R is the correct explanation of A.

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