Slide 1
... Use a magnetic field to create a current • emf (electromotive force) ~ potential difference • Where does the energy come from? → work ! ...
... Use a magnetic field to create a current • emf (electromotive force) ~ potential difference • Where does the energy come from? → work ! ...
Electricity and Magnetism - Unit 1
... battery, a photocell, or an electric generator at a power plant 2. Wires- connect the other parts of a circuit; made of conducting materials that have low resistance, such as copper ...
... battery, a photocell, or an electric generator at a power plant 2. Wires- connect the other parts of a circuit; made of conducting materials that have low resistance, such as copper ...
Document
... except that it includes the displacement current. • What is the displacement current? The equation is on the next page, but the physical meaning is that it’s not a true current, but rather a mathematical construction to deal with changes in electric flux. ...
... except that it includes the displacement current. • What is the displacement current? The equation is on the next page, but the physical meaning is that it’s not a true current, but rather a mathematical construction to deal with changes in electric flux. ...
Physics 122B Electromagnetism
... of iron is not a strong permanent magnet. It turns out, as shown in the figure on the right, that a piece of iron is divided into small regions called magnetic domains. A typical domain size is roughly 0.1 mm. The magnetic moments of all of the iron atoms within each domain are perfectly aligned, so ...
... of iron is not a strong permanent magnet. It turns out, as shown in the figure on the right, that a piece of iron is divided into small regions called magnetic domains. A typical domain size is roughly 0.1 mm. The magnetic moments of all of the iron atoms within each domain are perfectly aligned, so ...
Magnetic Field
... relative to each other for an electric current to be produced. • This causes the magnetic field inside the loop to change with time. • The generation of a current by a changing magnetic field is electromagnetic ...
... relative to each other for an electric current to be produced. • This causes the magnetic field inside the loop to change with time. • The generation of a current by a changing magnetic field is electromagnetic ...
Summary Sheets
... • Two north poles or two south poles repel each other. A bar magnet is a permanent magnet, because it is always magnetic. A wire with electricity flowing through it has a magnetic field around it. An electromagnet is a coil of wire with an electric current flowing through it. It is only magnetic whi ...
... • Two north poles or two south poles repel each other. A bar magnet is a permanent magnet, because it is always magnetic. A wire with electricity flowing through it has a magnetic field around it. An electromagnet is a coil of wire with an electric current flowing through it. It is only magnetic whi ...
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.