Magnetic Fields

The concept of magnetic field lines and magnetic fields was first studied and observed by Michael Faraday and by James Clerk Maxwell, who made great discoveries in the field of electromagnetism.
Magnetic fields are areas where an object produces a magnetic influence. The fields affect objects along things called magnetic field lines. A magnetic object can attract or push away another magnetic object. The amount of gravity is based on an object’s mass, while magnetic strength is based on the material that the object is made of.The direction of the field is the direction of the force on the north end of a magnet.

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A French scientist named Andre-Marie Ampere studied the relationship between electricity and magnetism. He discovered that magnetic fields are produced by moving charges. And these moving charges are affected by magnets. Stationary charges, on the other hand, do not produce magnetic fields, and are not affected by magnets. Two wires, with current flowing, when positioned next to each other, may attract or repel like two magnets.
A magnet creates a vector field, the magnetic field, at all points in the space around it. It can be described by measuring the force the field applies on a moving charged particle.The force (F) is equal to the charge (q) multiply by the speed of the particle times the magnitude of the field (B), or F = qv x B, where the location of F is at right angles to both v and B as a result of the cross product. This defines the magnetic field’s strength and direction at any point. The SI unit for magnetic field is the Tesla, (Newton x second)/(Coulomb x meter). A smaller magnetic field unit is the Gauss (1 Tesla = 10,000 Gauss).

Magnetic Field Lines

An advantage of using magnetic field lines can be specified completely and briefly using simple principles such as the number of field lines through a surface. These principles can be translatedin mathematical form. For example, the number of field lines through a given surface is the surface integral of the magnetic field.

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The direction of magnetic field linescharacterized by the alignment of iron filings sprinkled on paper placed above a bar magnet. Severalevents have the effect of showing magnetic field lines as though the field lines are physical occurrences. An example is an iron filings placed in a magnetic field line up to form lines that correspond to field lines.Magnetic fields lines are also visually shown in plasma particle dipole interactions which creates visible lines of light that line up with the local direction of Earth’s magnetic field.

The Earth’s Magnetic Field

The Earth’s magnetic field is comparable to that of a bar magnet slanted 11 degrees from the spin axis of the Earth.The angle at which the magnetic field lines intersect the surface of the earth is known as inclination angle. This angle ranges from 0 degrees at the equator to 90 degrees at the poles.The magnetic field differs in strength over the earth’s surface. It is strongest at the poles and weakest at the equator.

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