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Lenz's law

The magnetic flux through the loop increases according to the relation (see attachment for remainder of the question). a) What is the magnitude of the emf induced in the loop when t= 2.05? b) Is the direction of the current through R to the right or left?

Induction and Energy Transfer

A metal rod is forced to move constant velocity V along two parallel metal rails, connected with a strip of metal at one end. A magnetic field of magnitude B = .350T points out of the page. a) if the rails are separated by a 25.0 cm and the speed of the rod is 55.0 cm/s, what emf is generated? b) if the rod has a resista

Electromagnetic Induction: Induced EMF and current.

Two parallel loops of wire having the same common axis. the smaller loop of (raduis r ) and is above the larger loop (raduis R) by a distance X>>R. the magnetic field due to the counterclockwise current i in the larger loop is nearly uniform throughout the smaller loop. suppose that x is increasing at a constant rate dx/dt =

16 good questions on electromagnetism

(See attached file for full problem description with proper symbols and diagrams) --- 3.1 A long wire carries a current of 2 A along the +z axis. Calculate B in free space at (3,4,9). 3.2 Inside a long conductor of radius a, the magnetic field is H = 5 rho;/(2pi a2) a(phi) A/m. (a) Determine the current density J. (b) D


(See attached file for full problem description) --- Refer to diagram below: 1. Use thevenin's theorem to calculate the thevenin emf and impedance for the circuit contained in the box to the left of the terminals A&B. Assume that L is a pure inductor. 2. Sketch the complete thevenin circuit plus load and calculate:

Changing magnetic field

Transcranial magnetic stimulation (TMS) is a noninvasive method for studying brain function, and possibly for treatment as well. In this technique, a conducting loop is held near a person's head. When the current in the loop is changed rapidly, the magnetic field it creates can change at a rate of {see attachment}. This rapidly

Faraday's Law of Electromagnetic Induction 2

A constant magnetic field passes through a single rectangular loop whose dimensions are 0.35 m x 0.55 m. The magnetic field has a magnitude of 2.1 T and is inclined at an angle of 70° with respect to the normal to the plane of the loop. (a) If the magnetic field decreases to zero in a time of 0.52 s, what is the magnitud

Phasor Diagram for Synchronous Generator

A 60-Hz 24-kV 250-MVA Y-Connected salient-pole synchronous generator (Xd=1.75 per unit, Xq=1.40 per unit) is operating with a phase-A to a neutral voltage of 14 cos wt kV and a phase-A current of 5.75 cos wt kA; the currents and voltages are balanced at three-phase. The rotor angle is known to be wt+37 degrees. a) Draw a pha

Light and Electricity

1. A proton of charge + 1.6 x 10^(-19) C and mass 1.67 x 10(-27)kg is introduced into a region of B = 1.5 T with an initial velocity of 1.25 x 10^6 m/s perpendicular to B. What is the radius of the proton's path? 2. A coil 17 cm in diameter and wound with 12 turns of wire is placed with the plane of the coil at right angles t


A 25-turn circular coil of wire has diameter 1.00 m. It is placed with its axis along the direction of the Earth's magnetic field of 50.0 μT, and then in 0.200 s it is flipped 180°. An average emf of what magnitude is generated in the coil?


The magnetic field perpendicular to a circular loop of wire 17.6cm in diameter is changed from +0.510 T to -0.450 T in 117rms, where + means the field points away from an observer and - toward the observer. Calculate the induced emf.

Magnetic field : key information

A 6.30cm diameter wire coil is initially oriented so that its plane is perpendicular to a magnetic field of 0.740T pointing up. During the course of 0.130s, the field is changed to one of 0.310 T pointing down. What is the average induced emf in the coil?

bar sliding in a magnetic field on rails - Voltage induced

Imagine that we have two metal rails 20 cm apart connected by a light bulb. The rails are placed in a 1.0 T magnetic field oriented vertically downward. We then constrain a bar to slide on the rails toward the lightbulb in this magnetic field. How fast do we have to move the bar to put a voltage difference of 3.0 V across the

current in a 48.1 mH inductor changes with time

The current in a 48.1 mH inductor changes with time as I = bt^2 - at. With a = 2.7 A/s and b = 3 A/s^2, find the magnitude of the induced emf at t = .992 s. Units of V At what time is the emf zero? Units of s

Batteries and Circuits

PART ONE: A battery that supplies an emf of 6.0 V has an internal resistance of 0.20 ohm. It is connected to a load resistor of 8.8 ohms. The total Current in the entire circuit is: A) less than 0.25 A B) between 0.25 A and 0.50 A C) between 0.50 A and 1.0 A D) greater than 1.0 A PART TWO: A battery of fou

Calculating the induced emf.

The length of a conductor linking a magnetic field is 0.060m, and the flux density of the field is 0.040 N/Am The conductor is moving down through the flux with a velocity of 1.5 m/s. What is the induced emf?

Electromagnetic theory

A circular current loop made of flexible wire is located in a magnetic field B; you may keep B constant or vary it. Describe three ways an emf can be induced in the loop.