1. What is Magnetic Permeability?

Definition: Magnetic permeability (μ) measures a material's ability to support the formation of a magnetic field within itself.

Units: The SI unit for magnetic permeability is henry per meter (H/m).

2. Understanding the Units (H/m)

The units come from the formula:

Where:

• \( \mu \) — Magnetic permeability (H/m)
• \( B \) — Magnetic flux density (tesla)
• \( H \) — Magnetic field strength (A/m)

Breakdown: Since 1 tesla = 1 weber/m² and 1 henry = 1 weber/ampere, the units simplify to H/m.

3. Types of Magnetic Permeability

Details:

• Absolute permeability (μ): Measured in H/m
• Relative permeability (μ_r): Dimensionless ratio to vacuum permeability
• Vacuum permeability (μ₀): 4π×10^-7 H/m (exact value)

4. Using the Calculator

Tips: Enter magnetic flux density (B) in tesla and magnetic field strength (H) in A/m to calculate permeability in H/m.

5. Frequently Asked Questions (FAQ)

Q1: Why is permeability measured in H/m?
A: The unit comes from the relationship between magnetic flux (weber) and current (ampere), with 1 H/m = 1 T·m/A.

Q2: What's a typical permeability value?
A: Vacuum permeability is 1.256637062×10^-6 H/m. Iron can have μ around 6.3×10^-3 H/m.

Q3: How does relative permeability differ?
A: Relative permeability is dimensionless (μ_r = μ/μ₀), showing how much more permeable a material is than vacuum.

Q4: What materials have high permeability?
A: Ferromagnetic materials like iron, nickel, and cobalt have high permeability (μ_r >> 1).

Q5: Can permeability be less than μ₀?
A: Yes, diamagnetic materials have μ_r slightly less than 1 (μ slightly less than μ₀).