Magnetic lines form continuous closed loop. Why ?

Explanation

### Step-by-Step Text Solution

1. **Understanding Magnetic Field Lines**: Magnetic field lines represent the direction and strength of a magnetic field. They are visualized as lines that emerge from the North Pole of a magnet and enter the South Pole.

2. **Direction of Magnetic Field Lines**: Outside a magnet, the magnetic field lines travel from the North Pole to the South Pole. Inside the magnet, they travel from the South Pole back to the North Pole, thus forming a closed loop.

3. **Nature of Magnetic Poles**: A key characteristic of magnets is that they always have both a North Pole and a South Pole. Magnetic poles occur in pairs; it is impossible to have a magnetic monopole (a single North or South Pole) in isolation.

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