Out of the two magnetic materials. 'A' has relative permeability slightly greater than unity while 'B' has less than unity. Identify the nature of materials 'A' and 'B'. Will their susceptibilities be positive or negative?

Explanation

To solve the problem, we need to analyze the given information about the two magnetic materials, A and B, in terms of their relative permeability and susceptibility.

### Step-by-Step Solution:

1. **Understanding Relative Permeability**:
- Material A has a relative permeability (\( \mu_r \)) slightly greater than 1: \( \mu_r > 1 \).
- Material B has a relative permeability (\( \mu_r \)) less than 1: \( \mu_r < 1 \).

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