What is the nature of magnetic susceptibility and relative magnetic permeability `(mu_r)` in case of paramagnetic substances?

Explanation

To determine the nature of magnetic susceptibility and relative magnetic permeability (μ_r) in paramagnetic substances, we can follow these steps:

### Step 1: Understand Magnetic Susceptibility (χ)
Magnetic susceptibility (χ) is a dimensionless quantity that indicates how much a material will become magnetized in an applied magnetic field. It helps classify materials as paramagnetic, diamagnetic, or ferromagnetic.

### Step 2: Identify the Nature of χ for Paramagnetic Substances
For paramagnetic substances, the magnetic susceptibility (χ) is always positive. This indicates that these materials are attracted to magnetic fields. The positive value of χ signifies that the material will enhance the magnetic field within it when exposed to an external magnetic field.

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