PHY1033C/HIS3931/IDH 3931 : Discovering Physics
... wires [Ampère expt with 2 wires] - a current can magnetize an iron bar - permanent magnets must be made of molecules with tiny circulating currents that line up. • Earth is a permanent magnet due to circulating charged currents in its core ...
... wires [Ampère expt with 2 wires] - a current can magnetize an iron bar - permanent magnets must be made of molecules with tiny circulating currents that line up. • Earth is a permanent magnet due to circulating charged currents in its core ...
... We also learned in section 6.1.3 that a magnetic field can speed up or slow down an electron orbiting a nucleus. The change in m is opposite to the change in B and results in diamagnetism. We defined the magnetic dipole moment per unit volume as the magnetization of the material. The magnetization i ...
Electromagnetic Induction5
... • Magnetic materials tend to point in the north – south direction. • Like magnetic poles repel and unlike ones attract. • Magnetic poles cannot be isolated. • When a bar magnet of dipole moment m is placed in a uniform magnetic field B , then, a) The force on it is zero b) The torque on it is mxB c) ...
... • Magnetic materials tend to point in the north – south direction. • Like magnetic poles repel and unlike ones attract. • Magnetic poles cannot be isolated. • When a bar magnet of dipole moment m is placed in a uniform magnetic field B , then, a) The force on it is zero b) The torque on it is mxB c) ...
Advanced Higher Physics
... Magnetic flux, , is a measure of the magnetism in an area, given by – =BA ...
... Magnetic flux, , is a measure of the magnetism in an area, given by – =BA ...
Problem Set 8
... If a negatively charged particle enters a region of uniform magnetic field which is perpendicular to the particle’s velocity, will the KE of the particle increase, decrease, or stay the same. Explain your answer. (Neglect gravity.) Question C How can you tell whether moving electrons in a certain re ...
... If a negatively charged particle enters a region of uniform magnetic field which is perpendicular to the particle’s velocity, will the KE of the particle increase, decrease, or stay the same. Explain your answer. (Neglect gravity.) Question C How can you tell whether moving electrons in a certain re ...
Week 8 - Magnetic Field and Magnetic Forces
... A conducting bar with mass m and length L slides over horizontal rails that are connected to a voltage source. The voltage source maintains a constant current I in the rails and bar, and a constant, uniform, vertical magnetic field B fills the region between the rails. This is shown in figure 2 wher ...
... A conducting bar with mass m and length L slides over horizontal rails that are connected to a voltage source. The voltage source maintains a constant current I in the rails and bar, and a constant, uniform, vertical magnetic field B fills the region between the rails. This is shown in figure 2 wher ...
File
... field that exerts a force on the wire and causes the wire to change directions when the current flow changes directions. ...
... field that exerts a force on the wire and causes the wire to change directions when the current flow changes directions. ...
Electromagnetism
... As the rotor is horizontal a commutator inverts the direction of the current through the wire loops, modifying the polarity of the induced magnetic field. The process is thus again in the initial state and the cycles starts over. ...
... As the rotor is horizontal a commutator inverts the direction of the current through the wire loops, modifying the polarity of the induced magnetic field. The process is thus again in the initial state and the cycles starts over. ...
Magnetic field
A magnetic field is the magnetic effect of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude (or strength); as such it is a vector field. The term is used for two distinct but closely related fields denoted by the symbols B and H, where H is measured in units of amperes per meter (symbol: A·m−1 or A/m) in the SI. B is measured in teslas (symbol:T) and newtons per meter per ampere (symbol: N·m−1·A−1 or N/(m·A)) in the SI. B is most commonly defined in terms of the Lorentz force it exerts on moving electric charges.Magnetic fields can be produced by moving electric charges and the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property, their spin. In special relativity, electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic tensor; the split of this tensor into electric and magnetic fields depends on the relative velocity of the observer and charge. In quantum physics, the electromagnetic field is quantized and electromagnetic interactions result from the exchange of photons.In everyday life, magnetic fields are most often encountered as a force created by permanent magnets, which pull on ferromagnetic materials such as iron, cobalt, or nickel, and attract or repel other magnets. Magnetic fields are widely used throughout modern technology, particularly in electrical engineering and electromechanics. The Earth produces its own magnetic field, which is important in navigation, and it shields the Earth's atmosphere from solar wind. Rotating magnetic fields are used in both electric motors and generators. Magnetic forces give information about the charge carriers in a material through the Hall effect. The interaction of magnetic fields in electric devices such as transformers is studied in the discipline of magnetic circuits.