* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Magnetic field
Wireless power transfer wikipedia , lookup
Magnetorotational instability wikipedia , lookup
Electrostatics wikipedia , lookup
Maxwell's equations wikipedia , lookup
Electromotive force wikipedia , lookup
Friction-plate electromagnetic couplings wikipedia , lookup
Neutron magnetic moment wikipedia , lookup
History of electromagnetic theory wikipedia , lookup
Magnetic field wikipedia , lookup
Magnetic nanoparticles wikipedia , lookup
Hall effect wikipedia , lookup
Electricity wikipedia , lookup
History of electrochemistry wikipedia , lookup
Electric machine wikipedia , lookup
Magnetic monopole wikipedia , lookup
Earth's magnetic field wikipedia , lookup
Scanning SQUID microscope wikipedia , lookup
Electromagnetism wikipedia , lookup
Lorentz force wikipedia , lookup
Faraday paradox wikipedia , lookup
Superconductivity wikipedia , lookup
Magnetic core wikipedia , lookup
Magnetoreception wikipedia , lookup
Eddy current wikipedia , lookup
Galvanometer wikipedia , lookup
Superconducting magnet wikipedia , lookup
Magnetohydrodynamics wikipedia , lookup
Multiferroics wikipedia , lookup
Magnetochemistry wikipedia , lookup
Force between magnets wikipedia , lookup
It is a substance that contains a magnetic field. There are three primary types of magnets; Ferromagnetic- A substance that is naturally and permanently magnetic like iron. Paramagnetic- which becomes magnetic under the influence of a magnetic field. Electromagnet- Becomes magnetic under the influence of an electric current. Is no longer magnetic when electricity flow is stopped. Magnetic field =surrounds a magnet and can exert magnetic forces. Magnetic force =the force a magnet exerts on another magnet, on iron, or a similar metal, or on moving charges (magnetic force is one aspect of electromagnetic force) Fig. 35.1.1. Magnetic field lines – single magnet Fig. 35.1.2. Magnetic field lines – two magnets Iron filings lining up along the magnetic field A permanent magnet is a substance that holds a magnetic field indefinitely. Iron, Cobalt, and Nickel are the only substances that are naturally magnetic. But, Co and Ni are somewhat rare, so the vast majority of magnets are made of iron. Euro pennies have steel An electromagnet starts with a power source and a wire. Batteries/Electricity produce electrons. Flowing electrons produce an electric field, which induces a magnetic field. Electromagnetic devices are used to change electrical energy into mechanical energy. Examples of electromagnetic devices: electric motors, galvanometers, loud speakers. Electromagnets can easily be made at home with a copper wire, a nail, and a battery. Wrap the wire around the nail and hook it to the positive and negative ends of the battery. Suddenly the nail is magnetic and can attract iron objects. A magnetic field in a current carrying wire can be increased by wrapping the wire into a coil. This coil of wire is called a solenoid When a magnetic core is placed in a solenoid, an electromagnet is formed This is the basis of many electric motors. The magnetic field is a dipole field. That means that every magnet MUST have two poles, a positive (+) or negative (−) electrical charge (a north and a south pole). Electrical charges are called monopoles, since they CAN exist without the opposite charge. He discovered the connection between electricity and magnets by chance in 1820. As he prepared for one of his classes, he noticed that when he turned on the electric current in a wire, a compass needle that was on another experiment changed its position. When the electric current was turned off, the compass needle returned to its original position. This magnetic field forms circles around a straight wire carrying the current. Point your thumb in the direction of the current (which is toward the negative terminal) If you curl your fingers around the wire, the way your fingers curve is in the direction of the magnetic field. The opposite of an electromagnet is also true also! When a magnetic field rotates around a wire, it generates an electric current. A hand-cranked dynamo charges a battery for an emergency radio… Or you can have a hamster do it Use water or wind to turn magnets to generate electricity Closed-cycle pressurized water turbines An electric current flowing around a rod will make a magnet. It is called an electromagnet A moving magnetic field flowing around a wire will make electricity. It is called a generator Electricity and magnetism are both aspects of A. the north pole. B. the south pole. C. electromagnetic force. D. ferromagnetic material. Electricity and magnetism are both aspects of A. the north pole. B. the south pole. C. electromagnetic force. D. ferromagnetic material. When electric charges are moving through a wire, a magnetic field is created. The wires are made out of materials/metals that can be magnetized. A fan uses a rotating electromagnet to turn its blades. This is an example of A. magnetic poles. B. an electric motor. C. a galvanometer. D. a loudspeaker. A fan uses a rotating electromagnet to turn its blades. This is an example of A. magnetic poles. B. an electric motor. C. a galvanometer. D. a loudspeaker. A material such as iron that can be magnetized because it contains magnetic domains. A substance that reacts to magnetic fields, but does not remain so after the field is removed. Liquid Oxygen can remain suspended between two magnets. The Earth acts as a giant electromagnet. There is a swirling liquid iron-nickel outer core floating around a solid iron-nickel inner core. Electrons moving around in the liquid create an electric current. The moving current around the iron core makes for a giant magnetic field. This acts much like a magnet flowing around a wire, creating a strong magnetic field The Earth’s magnetic field protects us from harmful solar particles by deflecting or absorbing them. The aurora borealis is located at the north pole, because that is where the energized solar particles come shooting down into the atmosphere.