Permeability of free space is also known as _________

Question

Examoogle · Accepted Answer

Option A: Magnetic constant

Explanation & Concepts:
Permeability of free space, denoted by $\mu_0$, is a physical constant that describes the capability of a vacuum to allow magnetic lines of force to pass through it. It is universally referred to as the magnetic constant, representing the absolute magnetic permeability of classical vacuum.

Working Principle: In magnetostatics, $\mu_0$ acts as the constant of proportionality relating magnetic flux density $\mathbf{B}$ to magnetic field strength $\mathbf{H}$ in a vacuum through the relationship $\mathbf{B} = \mu_0 \mathbf{H}$. It dictates the strength of the magnetic force produced per unit current.

Key Formulas: $\mu_0 = 4\pi 	imes 10^{-7} 	ext{ H/m}$ — Permeability of free space (Magnetic constant); \mu_0 = \frac{1}{\varepsilon_0 c^2} — Relationship connecting permeability, permittivity, and speed of light; B = \mu_0 H — Relation between flux density $B$ and magnetic field intensity $H$ in free space

Key Points: The value of $\mu_0$ is approximately $4\pi 	imes 10^{-7} 	ext{ H/m}$ or $	ext{N/A}^2$.; The dimension of permeability is $[M^1 L^1 T^{-2} A^{-2}]$.; Relative permeability $\mu_r$ for free space or vacuum is exactly $1$.

Applications: Used in calculating inductance, magnetic force, and magnetic flux density in magnetic circuits.; Essential parameter in Maxwell's equations for calculating electromagnetic wave propagation speed.

Additional Info: Standard value: $\mu_0 \approx 1.25663706 	imes 10^{-6} 	ext{ H/m}$.. Option B (Electric constant) refers to the permittivity of free space $\varepsilon_0$.. Option C (Electrostatic constant) refers to Coulomb's constant $k_e = \frac{1}{4\pi\varepsilon_0}$.. Option D is an incorrect term non-standard for physical constants.

Answer: A is correct — Permeability of free space is defined as the magnetic constant, representing the physical constant $\mu_0$.

Exam Tip: Remember the dual pair: $\mu_0$ is the Magnetic constant (permeability), while $\varepsilon_0$ is the Electric constant (permittivity). They combine to set the speed of light: $c = \frac{1}{\sqrt{\mu_0 \varepsilon_0}}$.

Examoogle · Answer

Option B: Electric constant

Examoogle · Answer

Option C: Electrostatic constant

Examoogle · Answer

Option D: Magnetostatic constant

Correct Answer

Discussion (0)

Correct Answer

Related Questions

Discussion (0)