Nickel, iron and cobalt are magnetic metals. Most other metals, including gold, copper, silver and magnesium, are generally not magnetic, although some of these metals might become slightly magnetic if placed in a magnetic field.Know More
Magnets are created by heating a suitable metal enough to exceed the material’s Curie temperature. This aligns the small magnetic fields produced by the material, enabling them to work together. Over time, these individual magnetic fields, called domains, fall out of alignment, causing a magnet to demagnetize. Scientists can also make electromagnets by passing electric currents through coils of wire surrounding a metal object, such as a nail. This principle is used in most engines and turbines and during the production of electricity. Not all magnets are man-made, and some are naturally occurring. For example, the mineral lodestone is magnetic. One of the first magnetic substances discovered, lodestone was used to create early compasses.
The Earth’s magnetic field is produced by the movements of the inner core. Scientists believe that the core is composed primarily of iron and nickel, which are both magnetic. This magnetic field is what causes the needle of a compass to point north. Additionally, the planet’s magnetic field deflects the charged particles that stream from the Sun.Learn more about Magnetism
Magnetic declination, also called "magnetic variation," is the angle between magnetic North and true North on the horizontal plane. The angle is measured in minutes and degrees and is indicated by the Greek symbol delta. The angle varies with the passage of time and with changes of location on the earth's surface.Full Answer >
Each atom of iron has an unpaired electron whose spin can be lined up to that of the unpaired electron from a neighboring iron atom. The spinning of the charged electron creates a magnetic moment, which in turn can align with an external magnet, thus making iron magnetic. Atoms of wood do not have unpaired electron spins that can line up with a magnet, and so it is non-magnetic.Full Answer >
Unlike magnetic poles attract each other, and like magnetic poles repel each other. Magnets produce a magnetic field that is an area of magnetic force that determines whether the poles are attracted or repulsed.Full Answer >
Magnetism occurs when iron is present in metals, so metals can be non-magnetic when they don't contain iron. Although some metals are not magnetic, they still hold the properties of metal and are considered as such.Full Answer >