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EMF

Electromagnetic Induction and induced EMF

Magnetic resonance imaging (MRI) is a medical technique for producing pictures of the interior of the body. The patient is placed within a strong magnetic field. One safety concern is what would happen to the positively and negatively charged particles in the body fluids if an equipment failure caused the magnetic field to be sh

output EMF of a generator

(See attached file for full problem description) 4. The drawing below shows a plot of the output emf of a generator as a function of time t. The coil of this device has a cross-secontal area per turn of 0.040 m2 and contains 136 turns. Find a. the frequency of the generator in Herz b. the angular speed in rad/s c. the magnit

Capacity, charge and voltage

The radii of curvature of the spheres of a spherical capacitor is given and to find the charge, charge density and work done when it is connected to a battery. See attached file for full problem description.

Inductance of a Solenoid

A long solenoid of length 8m with a cross-sectional area of 5.0x10^-5 m^2 contains 52,000 turns. 1) Find the self-inductance of the solenoid, assuming that the core is air. 2) If the current in the winding starts at 0 A and is increased steadily to 1.5 A in a time of 0.20 sec, what is the EMF induced in the solenoid?

Generators and Motors

A rectangular loop with an area of 120 cm^2 is placed in a magnetic field of 1.3 × 10^-2T and rotated about its long axis at 5.0 Hz. What is the instantaneous emf generated at the instant when the normal to the loop makes an angle θ = 0.27^o with the magnetic field?

Electromagnetic Induction: Current in a rotating coil.

Consider a uniform, constant magnetic field pointing in the z-direction with a strength B_0. Put a square loop of wire with resistance R and side length l in the xy-plane at time t=o and spinning about the x-direction with a constant angular velocity omega. What is the current through the loop as a function of time?

Assorted Problem Set on Currents

1. a) The magnitude of the earth's magnetic field at the surface of the earth is slightly less than one gauss.( I answered False and the answer was true) b) The torque exerted on a current loop by a uniform field tends to orient the plane of the loop perpendicular to the magnetic field.(I answered false and the answer was tru

Voltage Across Capacitor

Determine vc(t) for t > 0. The voltage across the capacitor in Figure P5.32 (attached file) just before the switch is changed as shown in the attached file. vc(0-) = -7 V Io = 17 mA C = 0.55 μF R1 = 7 kΩ R2 = 3.3 kΩ

RL Circuits: Growth and decay of current in inductor

See attached circuit. Note current source is 2A,Resistors are 2 Ohms, Inductor 2H. Assume that the switch has been open for a long time and that it closes at t=0 sec. The switch remains closed thereafter. How do I solve for Vx(t) and Ix(t)?

Electromagnetic Induction: Induced EMF in a rotating loop

1. A rectangular loop with surface area A lies in the x,y-plane with two sides parallel to the x-axis and the other two parallel to the y-axis in the presence of a uniform magnetic field with a magnitude B directed along the positive x-axis. The loop is made to rotate around an axis that is parallel to the y-axis and bisects the

2 Problems

1. What is the definition of displacement current and how does it arise? Does displacement current have any real significance? Explain 2. Write down the maxwell's equations of electromagnetism, and state the laws they represent. Explain the meaning of all the symbols used.

RCL series circuit

When an RCL series circuit is connected to a 120 V rms 60 Hz line, the rms current is 11.0 A and the current leads the emf by 45 degrees. a) Find the power supplied to the circuit. b) What is the resistance? c) If the inductance is 0..05H, find the capacitance. d) What capacitance would you add, and how, to make the po

Calculating the current of a circuit

A 50.0 H inductor and a 12.5 ohm resistor are connected in a series. A power source of constant 22.5 volts is applied across the series RL circuit elements at time t=0. What is the current in the circuit 10.0 seconds after the power is applied?

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

Thevenin's

(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