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

Options

A. If both the assertion and reason are true and reason is a true explantion of the assertion.
B. If both the assertion and reason are true but the reason is not true the correct explantion of the assertion.
C. If the assertion is true but reason false
D. If both the assertion and reason are false.

Explanation

To analyze the assertion and reason given in the question, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that a linear solenoid carrying current is equivalent to a bar magnet.

### Step 2: Analyze the Solenoid
A linear solenoid is a coil of wire that generates a magnetic field when an electric current passes through it. The magnetic field inside the solenoid is uniform and directed along the axis of the solenoid, while outside it resembles the field of a bar magnet.

### Step 3: Visualize the Magnetic Field Lines
When current flows through the solenoid, the magnetic field lines emerge from one end (which we can consider as the north pole) and enter the other end (considered as the south pole). This is similar to the magnetic field lines of a bar magnet, which also emerge from the north pole and enter the south pole.

### Step 4: Compare the Magnetic Field Lines
The magnetic field lines of a solenoid and a bar magnet are indeed similar in shape and direction. Both have a similar pattern where the lines are denser inside the solenoid/bar magnet and spread out outside.

### Step 5: Evaluate the Reason
The reason states that the magnetic field lines of both the solenoid and the bar magnet are the same. This is true as both configurations exhibit similar magnetic field patterns.

### Step 6: Conclusion
Since both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion, we can conclude that both the assertion and reason are true, and the reason is the correct explanation for the assertion.

### Final Answer:
Both the assertion and reason are correct, and the reason is the correct explanation for the assertion.

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