(A) : A linear solenoid carrying current is equivalent to a bar magnet.
(R) : The magnetic field lines of both are same.

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 in the question.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "A linear solenoid carrying current is equivalent to a bar magnet."
- A linear solenoid is a coil of wire that generates a magnetic field when an electric current passes through it. The magnetic field produced by a solenoid has a distinct north and south pole, similar to that of a bar magnet.

2. **Understanding the Reason (R)**:
- The reason states that "The magnetic field lines of both are the same."
- When we visualize the magnetic field lines of a solenoid, they emerge from one end (the north pole) and loop around to enter the other end (the south pole), similar to the magnetic field lines of a bar magnet.

3. **Analyzing the Truth of the Statements**:
- The assertion is true because a solenoid does behave like a bar magnet when current flows through it. Both have a north and south pole.
- The reason is also true because the magnetic field lines of a solenoid and a bar magnet do indeed have similar patterns.

4. **Determining the Relationship**:
- Since the reason explains why the assertion is true (the similarity in magnetic field lines), we conclude that both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

5. **Final Conclusion**:
- Therefore, the correct answer is that both the assertion and the reason are true, and the reason is the correct explanation of the assertion.