Question

The $S.I$ unit of magnetic pole strength is
A) $A.{m^2}$
B) $A.{m^{ - 1}}$
C) $A.m$
D) $A/{m^2}$

Answer 1

We can proceed by writing the pole-power formula. We know that when both magnets are defined by equal and opposite poles, a measure of the force exerted by one face of a magnet on the face of another magnet, then the force is attractive by using the magnetic field formula that can derive the pole unit of S.I.

Useful formula:
Magnetic field formula,
$B = \dfrac{F}{m}$
Where,
$B$ magnetic field, $F$ force,$m$ pole strength

Complete step by step procedure:
The ability of a magnetic pole to produce a magnetic field around it is called magnetic pole strength.
According to that pole strength is the measure of the amount of force exerted by one of the poles of a magnet to a pole of another magnet. The force can be attraction and repulsion.
We know that magnetic field formula,
$B = \dfrac{F}{m}$
Rearranging the equation,
We get,
$m = \dfrac{F}{B}$

Now $F$ can be return as $qvB$
The perpendicular to both Velocity of the charge with magnetic force
$m = \dfrac{{qvB}}{B}$
Now cancelling $B$ we get,
$m = qv$ the unit is repressed by Ampere-meter
Magnetic pole strength is the strength of a magnetic pole to attract magnetic materials towards itself.
$S.I$unit of magnetic pole strength is Ampere-meter
Hence the option C is correct answer $Am$

Note: Depending on how the pole force is represented, there are two possible units for magnetic pole strength in SI units. If this is represented as the force per unit field B, the SI unit is the ampere-meter (A m). It can also be represented as the force per unit field H, where the SI unit is the weber (Wb).