Which of the following arrangements shows the schematic alignment of magnetic moments of anti - ferromagnetic substance?

Options

A.
B.
C.
D.

Answer

To solve the question regarding the schematic alignment of magnetic moments in an anti-ferromagnetic substance, we can follow these steps:

### Step 1: Understand the Types of Magnetic Substances
- **Ferromagnetic Substances**: In these materials, all magnetic dipoles are aligned in the same direction, resulting in a strong net magnetic moment.
- **Anti-ferromagnetic Substances**: In these materials, adjacent magnetic dipoles are aligned in opposite directions (up and down), which cancels out their magnetic moments, leading to a net magnetic moment of zero.
- **Ferrimagnetic Substances**: These have magnetic dipoles that are also aligned in opposite directions, but they are unequal in magnitude, resulting in a net magnetic moment.

### Step 2: Analyze the Options
- **Option 1**: Displays a random arrangement of magnetic moments, indicating a ferrimagnetic substance.
- **Option 2**: Shows all magnetic moments aligned in the same direction, indicating a ferromagnetic substance.
- **Option 3**: Also shows a random arrangement, indicating another ferrimagnetic substance.
- **Option 4**: Displays an alternating arrangement of magnetic moments (up and down), which is characteristic of anti-ferromagnetic substances.

### Step 3: Identify the Correct Answer
From the analysis of the options, the arrangement that shows the schematic alignment of magnetic moments of an anti-ferromagnetic substance is found in **Option 4**, where the moments are arranged in an alternating up and down pattern.

### Final Answer
The correct option that represents the schematic alignment of magnetic moments of an anti-ferromagnetic substance is **Option 4**.

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