Why Magnetic Field Lines Form Closed Loops

 

❓ Question

Given below are two statements:

(A): Magnetic monopoles do not exist.
(R): Magnetic field lines are continuous and form closed loops.

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🖼️ Question Image

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✍️ Short Explanation

This problem is based on:

👉 Magnetic field lines
👉 Magnetic monopoles
👉 Assertion-Reason concept.

Main idea:

Magnetic field lines always form closed loops because isolated magnetic poles do not exist.

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🔷 Step 1 — Understand Assertion (A) 💯

A magnetic monopole means:

$$\boxed{ \text{Isolated north pole or south pole} }$$

In nature, magnets always exist as dipoles:

$$\boxed{ N \text{ and } S \text{ together} }$$

Thus magnetic monopoles are not observed experimentally.

✔ Assertion (A) is correct.

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🔷 Step 2 — Understand Reason (R)

Magnetic field lines:

✔ Start from north pole outside magnet

✔ Enter south pole

✔ Continue inside magnet from south to north

Hence they form:

$$\boxed{ \text{Closed continuous loops} }$$

So Reason (R) is correct.

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🔷 Step 3 — Connection Between A and R

If magnetic monopoles existed:

❌ Magnetic field lines would start or end at isolated poles.

But magnetic field lines always form closed loops.

This directly indicates:

$$\boxed{ \text{Magnetic monopoles do not exist} }$$

Thus Reason correctly explains Assertion.

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🔷 Step 4 — JEE Trap Alert 🚨

❌ Electric field lines aur magnetic field lines ko same samajh lena

Remember:

Electric field lines

Start and end on charges.

Magnetic field lines

$$\boxed{ \text{Always closed loops} }$$

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✅ Final Answer

$$\boxed{{\displaystyle \text{Both (A) and (R) are correct and (R) is the correct explanation of (A)}}}$$

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