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Electricity & Magnetism

Electric and Magnetic Fields and Vectors

At one instant, the electric and magnetic fields at one point of an electromagnetic wave are: E = (220i + 300 j - 50 k) V/m and B = Bo(7.9 i - 7.9j + ak) muT 1. What is the value of a? 2. What is the value of Bo? 3. What is the Poynting vector at this time and position? Find the

Derivation of a Wave Equation about E,B & V,A

1. Derive wave equation (about E, B ) by using Maxwell`s equations. 2. Derive wave equation (about vector potential, scalar potential) by using Maxwell`s equations. There are no conditions (such as no charges or no current) given, which means I have to solve in a general form! ***I am currently using Reitz's book<Founda

Center of Mass and Magnetic Materials

1. how would you find the centre of mass of an irregularly shaped object which has an irregular mass distribution? Is it possible for the center of mass to be outside the object? Give an example. 2. describe the origins of magnetism at the atomic level and explain how it is possible for this atomic property to be detected on th

Physics: Find the Poynting vector

An infinite wire having current I oriented along z-axis passes through a small hole in a uniformly charged infinite plane at z = 0. The current is perpendicular to the charged plane (with charge density &#963;) . Find the Poynting vector in vacuum and explain the result.

Electric and Magnetic Fields and Angular Frequency

Write down the (real) electric and magnetic fields for a monochromatic plane wave of amplitude E_0 angular frequency w and phase angle zero that is traveling the in the (0,1,1) direction and polarised in the x-hat direction. Note: You are not given bold k or k so even the 'space' part has to be in terms of w. (see attached

Fields at an Interface

See attached file for complete formulation of the problem. The problem deals with the electric and magnetic field behavior at an interface. The first question asks to show that using Maxwell's equations we can obtain the wave equation for the fields. The second question asks as to draw the fields at the interface. The th

Grounded Metal Plates: Electricity, Magnetism and Waves

Two infinitely long, grounded metal plates , at y=0 and y = a, are connected at x = +/- b by metal strips maintained at constant potential, Vo (insulated at the corners). Find the potential inside the rectangular pipe. Please show: a) A sketch of the set up b) The general form of V(x,y) before any boundary condition have

The Polarization of Light

Please solve and explain Two pieces of Polaroid are held against the light. Can you look through them by themselves? When they are stacked on top of each other? What happens if you rotate one of the Polaroids while keeping the other one fixed. Explain why you observe a variation in transmitted light intensity.

Physics Problem - Electricity, Magnetism and Waves

The power rating on a light bulb indicates how much power it would dissipate when it is hooked up to the standard household voltage of 120 V (this rating does not mean that the light bulb always dissipates the same amount o power). A) How much power is dissipated in a light bulb that is normally rated at 60W, i instead we ho

Physics - Electricity, Magnetism and Waves

If a proton moved from 0 V potential to 10 V potential, would its potential energy increase or decrease? If an electron moved from 0 V potential to 10 V potential,would its potential energy increase or decrease? Explain.

Magnitude of velocity of a electron

An electron e= 1.6*10^-19C, m= 9.1*10^-31kg is accelerated through a potential difference of 2kV. It then passes into a magnetic field perpendicular to its path, where it moves in a circular arc of diameter 0.36m. 1.) What is the magnitude of the velocity of the electron in a magnetic field? 2.) What is the magnitude of t

An electron moves in a force field due to a uniform electric field E and a uniform magnetic fiedl B that is at right angles to E. Let E = jE and B = kB. Take the initial position of the electron at the origin with initial velocity vo = ivo in the x direction. Find the resulting motion of the particle. Show that the path of motion is a cycloid. x = a sin wt + bt y = a (1 - cos wt) z = 0

An electron moves in a force field due to a uniform electric field E and a uniform magnetic field B that is at right angles to E. Let E = jE and B = kB. Take the initial position of the electron at the origin with initial velocity vo = ivo in the x direction. Find the resulting motion of the particle. Show that the path of motio

Electric current: Drift Speed and the Current Density

1. A small but measurable current of 1.2X10^-10 A exists in a copper wire whose diameter is 2.5mm. The number of charge carriers per unit volume is 8.49X10^28 m^-3. Assuming the current is uniform, calculate the (a) current density and (b) electron drift speed. 2. Near Earth, the density of protons is the solar wind (a stream

Determining the Magnitude of an Electric Field

A long, thin straight wire linear charge density lamba runs down the center of a thin, hollow metal cylinder of radius R. The cylinder has a net linear charge density 2lamba. Assume lamba is positive. Please see attached file for additional information.

Motion of a charged particle in electric and magnetic field. Crossed Fields

Please review my solution to the problem and explain in detail what I may be doing wrong and what concepts I may not be applying correctly. I am not sure if I am apply the crossed fields concept correct in presuming that B is perpendicular. The problem states: An electron has an initial velocity of (12.0j + 15.0k) km/s

Electromagnetic Wave

** Please see the attached file for the full problem description ** 16. Which of the following expressions is correct for the transmitted intensity of an unpolarized beam of light with an intensity Ii passing through a polarizer 17. A certain part of the electromagnetic spectrum ranges from 200 nm to 400 nm. What is the hi

Calculate the Magnetic Field in Thomson's Experimentt.

When Thomson experimented with his apparatus, he noticed that in one run, the electron beam dropped 1.35 cm. when it emerged from the parallel plate region (where the electric and magnetic fields were present). If L = 5 cm, E = 1000 volts/meter, determine the value of the B-Field in Tesla. Should I use the equation B~Sq. Root

Monochromatic Plane Wave

Write the (real) electric and magnetic fields for a monochromatic plane wave of amplitude Eo, frequency w, and phase angle zero that is (a) traveling in the negative x direction and polarized in the z-direction; (b) traveling in the direction from the origin to the point (1,1,1), with polarization parallel to the xz plane. In ea

The drift velocity and Hall voltage.

The number density of free electrons in copper is 8.47 x 10 ^22 electrons per cubic centimeter. If a metal strip of copper 2 cm by 0.1 cm (thickness), magnetic field pointing up to top of paper, and a current og 10A, fins a) the drift velocity Vsubd and b) the Hall voltage (Assume the magnetic field is 2.0 T.)

Finding the force on the electron

An electron that has velocity v = (2.0 x 106 m/s)i + (3.0 x 106 m/s) j moves through the uniform magnetic field B = (0.030 T)i - (0.15 T)j. a) Find the force on the electron. b) Repeat your calculation for a proton having the same velocity.

Electron in a magnetic field, Potential due to a charged rod

3) The uniform 30 mT magnetic field in figure 3 (see attachment) points in the positive z-direction. An electron enters the region of magnetic field with a speed of 5.0 * 10^6 m/s and at an angle of 30 degrees above the xy-plane. Find the radius "r" and the pitch "p" of the electron's spiral trajectory. 4) Figure 4 shows

Multipole expansion of the electric potential

Obtain an Approximate Electric Potential, Y (r), At a Large Distance, r >> a, From a Distribution Of Charges, Where the Multipole Expansion Of V (r) Includes Only the First Two Terms, the Monopole And the Dipole Term. See attached file for full problem description and diagrams.

Simple waves problem

(See attached files for full problem descriptions) 1. a. What are the three longest wavelengths for standing waves on a 240 cm long string that is fixed at both ends? b. If the frequency of the second longest wavelength is 50 Hz, what is the frequency of the third longest wavelength? 2. A sheet of glass is coated with 500