A maceral is a component, organic in origin, of coal or oil shale.

A machine is a human-made device that uses power to apply forces and control movement to perform an action.

Machine learning is the study of computer algorithms that improve automatically through experience and by the use of data.

All machinery spaces of category A and all other spaces containing propulsion machinery, boilers, oil fuel units, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing....

Those spaces and trunks to such spaces which contain either: 1. Internal combustion machinery used for the main propulsion, 2. Internal combustion machinery used for purpose other than...

Hot, thick, molten (liquid) rock found beneath the Earth's surface; formed mainly in the mantle.

A nondestructive examination of steel for surface and subsurface defects employing a dry or wet iron powder and a source setting up magnetic fields in the metal.

A magnet is a material or object that produces a magnetic field.

Magnet wire or enameled wire is a copper or aluminium wire coated with a very thin layer of insulation. It is used in the construction of transformers, inductors, motors, generators and other applications that require tight coils of insulated wire.

A magnetic circuit is made up of one or more closed loop paths containing a magnetic flux.

Magnetic confinement fusion is an approach to generate thermonuclear fusion power that uses magnetic fields to confine fusion fuel in the form of a plasma.

Magnetic energy and electrostatic potential energy are related by Maxwell's equations.

Magnetic particle Inspection (MPI) is a non-destructive testing (NDT) process for detecting surface and shallow subsurface discontinuities in ferromagnetic materials such as iron, nickel, cobalt, and some of their alloys.

A nondestructive testing technique using a mixture of iron filings in thin white paint which is spread over the surface to be examined.

Magnetic susceptibility is a measure of how much a material will become magnetized in an applied magnetic field.

Magnetism is a class of physical phenomena that are mediated by magnetic fields. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomenon of electromagnetism.

Magnetite is a mineral and one of the main iron ores.

Magnetization is the vector field that expresses the density of permanent or induced magnetic dipole moments in a magnetic material.

A magneto is an electrical generator that uses permanent magnets to produce periodic pulses of alternating current.

In physics, a ferromagnetic material is said to have magnetocrystalline anisotropy if it takes more energy to magnetize it in certain directions than in others.