Electromagnetism: What You Need to Know
... By now, you should know something about what goes on inside a wire when there is a direct current (DC) passing through it: electrons flow, they have energy, and eureka! the light bulb turns on. Equally exciting, however, is what occurs OUTSIDE of the wire. As the current runs through a wire, a magne ...
... By now, you should know something about what goes on inside a wire when there is a direct current (DC) passing through it: electrons flow, they have energy, and eureka! the light bulb turns on. Equally exciting, however, is what occurs OUTSIDE of the wire. As the current runs through a wire, a magne ...
Faraday`s Law of Induction
... magnetic field around a closed loop is proportional to the electric current flowing through the loop. This is useful for the calculation of magnetic field for simple geometries. ...
... magnetic field around a closed loop is proportional to the electric current flowing through the loop. This is useful for the calculation of magnetic field for simple geometries. ...
Magnetism K-3 Teacher Guide
... Things that are made with iron, nickel and cobalt will be attracted to a magnet. Most other metals are not magnetic. Aluminum, copper, and magnesium are not magnetic. Precious metals like gold and silver are not magnetic. The atoms that make up iron, nickel and cobalt, can all be aligned in the same ...
... Things that are made with iron, nickel and cobalt will be attracted to a magnet. Most other metals are not magnetic. Aluminum, copper, and magnesium are not magnetic. Precious metals like gold and silver are not magnetic. The atoms that make up iron, nickel and cobalt, can all be aligned in the same ...
Magnets Hold a refrigerator magnet close to your refrigerator door
... refrigerator door. Let go of it. If you are close enough to the refrigerator, the magnet will jump across empty space and stick to the refrigerator. This action might seem kind of mysterious. But it makes sense when you know what magnetism is. Magnetism is an invisible force. Magnetic force can attr ...
... refrigerator door. Let go of it. If you are close enough to the refrigerator, the magnet will jump across empty space and stick to the refrigerator. This action might seem kind of mysterious. But it makes sense when you know what magnetism is. Magnetism is an invisible force. Magnetic force can attr ...
Applications
... • If you pass current through a loop of wire. you get a magnet Î Oersted’s discovery • Basic laws of magnetism Îelectric currents produce magnetic fields (Ampere) Îmagnetic field lines are always closed loops • permanent magnets: the currents are atomic currents – due to electrons spinning in atomst ...
... • If you pass current through a loop of wire. you get a magnet Î Oersted’s discovery • Basic laws of magnetism Îelectric currents produce magnetic fields (Ampere) Îmagnetic field lines are always closed loops • permanent magnets: the currents are atomic currents – due to electrons spinning in atomst ...
Sources of Magnetic Field
... • In order to have a meter with a linear scale, the field lines in the gap should be always parallel to the plane of the coil as it rotates. • This could be achieved if we have a radial magnetic field. The soft iron cylinder gives us this field shape. ...
... • In order to have a meter with a linear scale, the field lines in the gap should be always parallel to the plane of the coil as it rotates. • This could be achieved if we have a radial magnetic field. The soft iron cylinder gives us this field shape. ...
Discussion Explicit Calculations
... 5. Starting from Maxwell’s equations in a linear medium with magnetic permeability µ and dielectric constant , (i) derive the boundary conditions that electric and magnetic fields should satisfy at the boundary connecting two different media. (10 points) (ii) the reflection and transmission coeffic ...
... 5. Starting from Maxwell’s equations in a linear medium with magnetic permeability µ and dielectric constant , (i) derive the boundary conditions that electric and magnetic fields should satisfy at the boundary connecting two different media. (10 points) (ii) the reflection and transmission coeffic ...
Force between magnets
Magnets exert forces and torques on each other due to the complex rules of electromagnetism. The forces of attraction field of magnets are due to microscopic currents of electrically charged electrons orbiting nuclei and the intrinsic magnetism of fundamental particles (such as electrons) that make up the material. Both of these are modeled quite well as tiny loops of current called magnetic dipoles that produce their own magnetic field and are affected by external magnetic fields. The most elementary force between magnets, therefore, is the magnetic dipole–dipole interaction. If all of the magnetic dipoles that make up two magnets are known then the net force on both magnets can be determined by summing up all these interactions between the dipoles of the first magnet and that of the second.It is always more convenient to model the force between two magnets as being due to forces between magnetic poles having magnetic charges 'smeared' over them. Such a model fails to account for many important properties of magnetism such as the relationship between angular momentum and magnetic dipoles. Further, magnetic charge does not exist. This model works quite well, though, in predicting the forces between simple magnets where good models of how the 'magnetic charge' is distributed is available.