Question

Find the symbols that have standard meanings.
(A). electric field $E$.
(B). magnetic field $B$.
(C). magnetic permeability ${\eta _0}$ and the relevant equation

Answer 1

In this question, the concept of electric field, magnetic field, and magnetic permeability will be used. That is, the electric field is equal to the force per unit charge and it is inversely proportional to the electric charge. The magnetic field is the field due to charge carriers in motion. The magnetic permeability of a magnetic field associated with the magnetic field.

Complete step by step answer:
(A).
We are given the parameter electrical field. As we know, the electrical field can be defined as the region around an electric charge in which an electric force is exerted on another charge. And the electric charge is represented by $\left( q \right)$ and the force is represented by $F$ and the electric field is represented by $E$. The direction of the electric field is to the force it would exert on a positive charge.
The formula for the electrical field is,
$E = \dfrac{F}{q}\;{\text{Volt/meter}}$

The SI unit for electrical field is volt per meter $\left( {{\text{Volt/meter}}} \right)$, and which is equivalent to the newtons per coulomb $\left( {{\text{N/C}}} \right)$.

(B).
We are given the parameter magnetic field. The magnetic field is defined as the field produced by electric charges in motion or by the current flows. It is the field of force on material like iron when placed in the vicinity of the field, and it does not require any medium to propagate, and the magnetic field has the greatest energy storing capacity than the electrical field.

The formula for magnetic field,
$B = \dfrac{{{\mu _0}I}}{{2\pi r}}{\text{Tesla}}$

Where, $I$ is the current flowing in the straight wire, $r$ is the shortest distance. And ${\mu _0}$ is the basic constant in nature that is related to the speed of the light. The SI unit magnetic field is $\left( {{\text{Tesla}}} \right)$.

(C).
We are given the parameter magnetic permeability.

The magnetic permeability is the permeability in electromagnetism and that is the property of a magnetic material which supports the formation of a magnetic field. And we can say the magnetic permeability of a material is associated with the magnetization capability of the material.
The formula for magnetic permeability is,
${\eta _0} = \dfrac{B}{H}$

Where, ${\eta _0}$ represents the magnetic permeability of the material and $B$ is the magnetic flux density and $H$ is the magnetic field strength of the material. And magnetic permeability is the scalar quantity.
The SI unit of the Magnetic permeability is Henries per metre$\left( {{\text{H/m}}} \right)$ or we can write as newtons per ampere square $\left( {{\text{N}} \cdot {{\text{A}}^{{\text{ - 2}}}}} \right)$.

Note: There should be no confusion between the symbol of magnetic field and the magnetic field density. The magnetic permeability is the scalar quantity which does not depend on the direction.