Magnetic Field

on . Posted in Electromagnetism

Magnetic field, abbreviated as B, exerts an invisible force that substances are sensative to magnetism.  Magnetic fields never cross, never start or stop, where the field is strongest, lines bunch togeather and can be seen clearly seen in the real world.  A magnetic field is a region in space where a magnetic force can be detected.  It is produced by the movement of electric charges, such as electrons in atoms or current carrying wires.  The magnetic field is a vector, having both magnitude and direction and can exert forces on other magnetic objects or moving charges.

Magnetic fields are associated with magnets and electric currents.  When a magnetic material, such as iron or a magnetized object, is placed in a magnetic field, it experiences a magnetic force and can be attracted or repelled.  This property is the basis for the interaction between magnets and other magnetic materials.  Magnetic fields are typically represented by magnetic field lines or flux lines.  These lines provide a visual representation of the direction and strength of the magnetic field.  The density of the lines indicates the strength of the field, with closer lines indicating a stronger field.

The behavior of magnetic fields can be described by several fundamental principles

• Magnetic field lines form closed loops  -  Magnetic field lines always form continuous closed loops.  They originate from the north pole of a magnet and terminate at the south pole, creating a continuous path for the magnetic field.
• Magnetic field lines never intersect  -  Magnetic field lines never cross or intersect each other.  If they did, it would imply that a point in space could have multiple directions of magnetic field, which is not possible.
• Magnetic field strength decreases with distance  -  The strength of a magnetic field decreases as you move farther away from its source.  This decrease follows an inverse square law, similar to the behavior of electric fields.

Magnetic fields have numerous applications in various fields, including electromagnetism, electrical engineering, and medical imaging.  They are essential for generating electric power, transmitting electrical signals, and operating devices such as motors, generators, transformers, and magnetic resonance imaging (MRI) machines.

Magnetic Field Formula

$$B = \mu \; I \; N\;/\;l$$     (Magnetic Field)

$$\mu = B \; l \;/\; I \; N$$

$$I = B \; l \;/\; \mu \; N$$

$$N = B \; l \;/\; \mu \; I$$

$$\ l = \mu \; I \; N \;/\; B$$

Solve for B

 permeability, u current intensity, I number of wire turns, N length of solenoid, l

Solve for u

 magnetic field, B length of solenoid, l current intensity, I number of wire turns, N

Solve for I

 magnetic field, B length of solenoid, l permeability, u number of wire turns, N

Solve for N

 magnetic field, B length of solenoid, l permeability, u current intensity, I

Solve for l

 permeability, u current intensity, I number of wire turns, N magnetic field, B

Symbol English Metric
$$B$$ = magnetic field - $$kg\;/\;s^2-A$$
$$\mu$$  (Greek symbol mu) = permeability - $$m^2$$
$$I$$ = current intensity flowing in the cable - $$C\;/\;s$$
$$N$$ = number of turns of the wire $$dimensionless$$
$$l$$ = length of the solenoid - $$mm$$

Tags: Electrical Magnetic