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Below you will find some commonly asked questions about magnets and magnetism. If you don’t find the answers you’re looking for, please contact us.
What is a magnet? At its most basic level, a magnet is an object that is made of materials that create a magnetic field. Magnets have poles, at least one north pole and one south pole. What is a magnetic field? A magnetic field is the region in space where a magnetic force can be detected. The magnetic field strength and direction can be measured in terms of strength and direction. What is magnetism? Magnetism is the force of attraction or repulsion between substances made of certain materials, such as iron, nickel, cobalt, and steel. The force of magnetism, simply put, is due to the motion of electric charges. What are magnets attracted to? Magnets are attracted to three types of metals only-nickel, iron, and cobalt. What are some uses for magnets? Magnets are in most electronic devices, anything that has a motor uses a magnet. TV’s, computers, fax machines, microwave ovens, all operate with magnets. Magnets are used to keep refrigerator doors closed, are mounted on trucks that clean roadways, are placed in cows stomachs to catch metals, in medical devices to create a magnetic picture, in trains, and used to slow down roller coasters and subways, and in countless other devices. More uses of magnets are found everyday. What are permanent magnets made of? Today’s permanent magnets are made of alloys. Alloy materials include • Aluminum-Nickel-Cobalt (Alnico) • Neodymium-Iron-Boron (Neodymium magnets or "super magnets", a member of the rare earth category) • Samarium-Cobalt (a member of the rare earth category) • Strontium-Iron (Ferrite or Ceramic) How are magnets made? Magnets are made from materials that contain nickel, iron, or cobalt. When these materials are exposed to a magnetic field, the structure of the material is actually changed on a microscopic level. The molecules are rearranged into lines {called polarized). When enough of the metals are polarized, it becomes a magnet. What are magnetic poles? All magnets have points, or poles, where their magnetic strength is concentrated. Those points are called poles. We label them north and south because suspended magnets orient along north-south planes. On different magnets, like poles repel each other, opposite poles attract. What is the difference between the north and south poles of a magnet? When suspended or allowed to rotate freely, magnets orient themselves in a north-south direction. The end of a magnet that points to the north is called the north pole. The point that seeks the south is called the south pole. Is there a simple way to tell which end of a magnet is the north pole? Both poles of a magnet look the same. However, if you place a compass near a magnet, the needle that normally points toward the north pole of the earth moves in the direction of the magnet’s south pole. Is it true that magnetic fields are stronger closer to the magnets themselves? Yes. The strength of magnetic fields diminishes with distance. This phenomenon can be measured with exponential equations. What is the difference between permanent magnets and electromagnets? Permanent magnets emit a magnetic field without the need for any external source of power. An electromagnet emits a magnetic field only when an electrical current runs through it. Are permanent magnets really permanent? Magnets generally retain their magnetism unless they are stored near power lines, other magnets, and high temperatures. Over time, magnet materials lose a very small amount of magnetism. For example, Samarium Cobalt magnets may lose about 1% of their magnetism in ten years. Do magnets get weaker? How? Several factors can weaken the magnetism in a magnet. If a magnet is stored close to heat, strong electrical currents, other magnets, or radiation, it can lose its strength. Additionally, high humidity can corrode neodymium magnets. Can magnets be made stronger? Once a magnet is fully magnetized, it cannot be made any stronger. What kind of magnets are the strongest? Rare earth magnets (Neodymium and Samarium Cobalt) are the strongest. How do I repair my de-magnetized compass? If your compass becomes demagnetized (points in the wrong direction), place the South Pole of a magnet directly on top of the compass needle. Slowly slide the bar magnet along the red side of the needle, toward the pointed end, and then down the side of the compass. Pull the magnet away and your compass is re-magnetized.
All animals including humans have small magnetite crystals in their brains. Scientists believe that animals may navigate or migrate by sensing the pull of the crystals towards the earth’s magnetic poles. The earth is a big magnet. Liquid metals deep within the earth create convection currents which in turn create the magnetic force. It is believed that the magnetic force surrounding the earth makes life possible. Without the “magnetic force field” too much energy would reach us from the sun and would wipe out our atmosphere. All electricity is made from magnets. When a magnet is spun inside a coil of wire, electrons start to flow from the wire. All power plants use fuel to spin magnets. Never! Place a magnet near computers, television, watches, clocks, tapes, videos, credit cards. It may damage or distort in some way. |
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