Question

Which of the following is NOT a unit of permeability?

• A. \( \text{Henry meter}^{-1} \)
• B. \( \text{Weber ampere}^{-1} \text{ meter}^{-1} \)
• C. \( \text{Ohm second meter}^{-1} \)
• D. \( \text{Volt second meter}^{-1} \)

Hint:

To check valid units, use the SI unit relationships of permeability: \( \mu = \frac{\text{Henry}}{\text{Meter}} \).

Answer 1

The Correct Option is D

Step 1: Permeability (\( \mu \)) 

Permeability (\( \mu \)) is defined in terms of SI units as:

\[ \mu = \frac{\text{Weber}}{\text{Ampere} \cdot \text{Meter}} \]

Thus, valid units include:

• \( \text{Henry meter}^{-1} \)
• \( \text{Weber ampere}^{-1} \text{ meter}^{-1} \)
• \( \text{Ohm second meter}^{-1} \)

Step 2: Invalid Unit

The unit "Volt second meter\(^{-1}\)" is not a valid unit of permeability.