Relative permeability of vacuum is__________?
Correct answer: A. 1
- A. 1
- B. 1 H/m
- C. 1/4JI
- D. 4n x 10-' H/m
Explanation
Relative permeability is defined as μr = μ/μ0, so vacuum has μ = μ0 and therefore μr = 1. The value 4π × 10⁻⁷ H/m is the absolute permeability of free space, not its relative permeability.
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