Producing Electric Current
... When the coil is fixed and the magnet rotates, the current is the same as if the coil rotates and the magnet is fixed. Construction of a generator in a power plant Electromagnets contain coils of wire wrapped around ...
... When the coil is fixed and the magnet rotates, the current is the same as if the coil rotates and the magnet is fixed. Construction of a generator in a power plant Electromagnets contain coils of wire wrapped around ...
Physics 2102 Spring 2002 Lecture 4
... charges are all on the surface. The charges produce an electric field outside the conductor. On the surface of conductors in electrostatic equilibrium, the electric field is always perpendicular to the surface. Why? Because if not, charges on the surface of the conductors would move with the electri ...
... charges are all on the surface. The charges produce an electric field outside the conductor. On the surface of conductors in electrostatic equilibrium, the electric field is always perpendicular to the surface. Why? Because if not, charges on the surface of the conductors would move with the electri ...
Electric Current
... What makes the light bulb glow? Like water current, electric current can be slowed down by bumping into things The part of the circuit which is inside of the light bulb is a thin wire called a filament. This filament resists the flow of electrons; The electrons bump into the molecules in the materi ...
... What makes the light bulb glow? Like water current, electric current can be slowed down by bumping into things The part of the circuit which is inside of the light bulb is a thin wire called a filament. This filament resists the flow of electrons; The electrons bump into the molecules in the materi ...
Electricity and Magnetism
... Electromagnets Magnetic field is present only when current is flowing in the wire coil Increase strength of the magnetic field by adding coils to the wire or increasing the current flowing through the wire Magnetic properties of electromagnets can be controlled by changing the electric current flow ...
... Electromagnets Magnetic field is present only when current is flowing in the wire coil Increase strength of the magnetic field by adding coils to the wire or increasing the current flowing through the wire Magnetic properties of electromagnets can be controlled by changing the electric current flow ...
Bfield2CT
... B2-8.A row of positive charges is stationary on the ground. A person with a gauss-meter(which measures the magnetic field) is running to the right along the row of charges, at the same height as the charges and in front of them (in the diagram below). What is the direction of the B-field which the ...
... B2-8.A row of positive charges is stationary on the ground. A person with a gauss-meter(which measures the magnetic field) is running to the right along the row of charges, at the same height as the charges and in front of them (in the diagram below). What is the direction of the B-field which the ...
CONDUCTORS AND INSULATORS
... applications. Constant spacing between two conductors through the entire length provides a transmission line. Common examples are the coaxial cable, the twin lead and ribbon cable. The coaxial cable with outside diameter of 1/4 inch is generally used for the signals in cable television. In construct ...
... applications. Constant spacing between two conductors through the entire length provides a transmission line. Common examples are the coaxial cable, the twin lead and ribbon cable. The coaxial cable with outside diameter of 1/4 inch is generally used for the signals in cable television. In construct ...
Lecture 7: Transmission Line Parameters
... attenuate the transient voltages/currents that arise during a lighting strike. The ground wire is typically grounded at each pole. • Corona discharge: Due to high electric fields around lines, the air molecules become ionized. This causes a crackling sound and may cause the line to glow! ...
... attenuate the transient voltages/currents that arise during a lighting strike. The ground wire is typically grounded at each pole. • Corona discharge: Due to high electric fields around lines, the air molecules become ionized. This causes a crackling sound and may cause the line to glow! ...
Motors and Generators Revision for Trials
... magnetic field created by curved pole-pieces, because maximum emf is induced for more time as the rotor is turned through the field. Another improvement would be to increase the number of loops upwards from 54. d) V = I R 18 = 450 I I = 4.0 10-2 A FB = B I ℓ sin θ FB = 0.22 4.0 10-2 ...
... magnetic field created by curved pole-pieces, because maximum emf is induced for more time as the rotor is turned through the field. Another improvement would be to increase the number of loops upwards from 54. d) V = I R 18 = 450 I I = 4.0 10-2 A FB = B I ℓ sin θ FB = 0.22 4.0 10-2 ...
RESISTIVITY Objective Objective of this lab work is to measure
... Fig. 1. (a) A conductor of cylindrical shape has length L and area of cross-section A. Since crosssection is uniform over the whole length of this conductor, its resistance can be found using formula (2). (b) R can be found experimentally by measuring the voltage V across the conductor and current I ...
... Fig. 1. (a) A conductor of cylindrical shape has length L and area of cross-section A. Since crosssection is uniform over the whole length of this conductor, its resistance can be found using formula (2). (b) R can be found experimentally by measuring the voltage V across the conductor and current I ...
Interactions between Electricity and Magnetism
... Mag/Elec Interactions Electro-magnets If you coil a wire into a helical form (like wrapping a wire around a cylinder) and run a current through it, each circular coil creates a small mag field. The mag field from each coil “adds up” to create what looks like a magnet with a North and South po ...
... Mag/Elec Interactions Electro-magnets If you coil a wire into a helical form (like wrapping a wire around a cylinder) and run a current through it, each circular coil creates a small mag field. The mag field from each coil “adds up” to create what looks like a magnet with a North and South po ...
PHYS_3342_100611
... Semiconductor have very different electric properties. As T increases, concentration of Free electrons goes up dramatically, decreasing resistivity Most importantly – current strength is not linearly proportional to voltage (diode) ...
... Semiconductor have very different electric properties. As T increases, concentration of Free electrons goes up dramatically, decreasing resistivity Most importantly – current strength is not linearly proportional to voltage (diode) ...
Thermal Agitation of Electric Charge in Conductors
... that such quantities as charge, number, and mass of the carriers of electricity do not appear explicitly in the formula for electromotive force These quantities inHuence R„however, and, therefore, enter indirectly. It is instructive to consider the equilibrium between the thermal agitation of the ca ...
... that such quantities as charge, number, and mass of the carriers of electricity do not appear explicitly in the formula for electromotive force These quantities inHuence R„however, and, therefore, enter indirectly. It is instructive to consider the equilibrium between the thermal agitation of the ca ...
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Skin effect
Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor. The electric current flows mainly at the ""skin"" of the conductor, between the outer surface and a level called the skin depth. The skin effect causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller, thus reducing the effective cross-section of the conductor. The skin effect is due to opposing eddy currents induced by the changing magnetic field resulting from the alternating current. At 60 Hz in copper, the skin depth is about 8.5 mm. At high frequencies the skin depth becomes much smaller. Increased AC resistance due to the skin effect can be mitigated by using specially woven litz wire. Because the interior of a large conductor carries so little of the current, tubular conductors such as pipe can be used to save weight and cost.