Electromagnetism & optics

2. a. A fixed volume charge distribution of constant charge density p_0 is contained within a rectangular box centered at the origin of a Cartesian coordinate system (x, y, z). The box has dimensions w X w X d, where d << w ( i.e. you can model the sheet as infinite in the x and y directions). i) Find the total charge insid ...continues

Determining the resistance of resistors in a parallel circuit

When three resistors R1, R2 and R3 are connected in parallel as shown in the diagram. *Please see the attached MS Word document for the diagram. a. Derive a rule to estimate the network resistance when one of the resistors has a much smaller resistance than the other two. b. Derive a rule to estimate the network resi ...continues

Gauss' Law, Faraday's Law, and Ampere's Circuit Law

I need help with the attached electromagnetism and optics questions. Please see the attached PDF document for questions relating to Gauss' Law, Faraday's Law, and Ampere's Circuit Law. ￼Thank you.

Electrostatic potential

3. (a) Four point charges are placed at the vertices of a square as shown in the diagram. The charges are of equal magnitude, Q, the sign of each charge is given in this diagram (attached). (i) What is the value of V x E at all spatial points in this conﬁguration of charges (note that the charges are stationary)? What is t ...continues

Maxwell's equation

2. (a) (i) Write down Maxwell's equations for static electric and magnetic ﬁelds in the vacuum (note that you should include charge and current densities). (ii) How did Maxwell modify Ampére's law to account for dynamic electric ﬁelds? (b) In a region of space in which the relative permittivity is (attached equation), ...continues

Electromagnetism and Optics

The diagrams attached represent the polarization states of light. In each case the wave is traveling along the x-axis in the positive x direction. i) Which diagram represents linear polarized light at 45 degrees? ii) Which diagram represents left circular light? Explain. iii) Which diagram represents un-polarized light? ...continues

Total charge in coulombs

I need help with this problem: Calculate the total charge in coulombs on an object with a net charge of 1.5E3 elemental charges.

A proton in a well

The figure [attached] shows electric potential V along an x axis. A proton is to be released at x = 3.5 cm with initial kinetic energy 3.5 eV. The scale of the vertical axis is set by Vs = 10.0 V. (a) If it is initially moving in the negative direction, it either reaches a turning point (if so, what is the x coordinate of th ...continues

Expression of an Electric Field

Hello Dr. Shafrir, I have another problem from our problem set that I was having trouble with as well, that I was hoping you could explain. For finding the electric field it would be the same everywhere correct, considering the field near each rod is the same? So I was thinking this was an application to Gauss's law and the ...continues

Physics: Find the electric field on any point on a y-axis and find the electric field as a function of the radial distance.

Hello Dr. Shafrir, can you please help with these two problems: 5.) A square of paper measuring a on a side carries a total charge +q which is uniformly distributed over its surface. The square lies in the x-y plane with its center at the origin and its sides parallel to the coordinate axes. Find the electric field on any poi ...continues

Electric Charge : Electrons and net attraction

1.) When you pull two socks out of a clothes dryer they stick to each other due to an accumulation of static charge. How many electrons are responsible for this net attraction? Let?s make an estimate following these steps: A sock has a mass of about 15g. How large (in newtons) is the gravitational force on one sock? Assumi ...continues

Diffusion equation

The one-dimensional neutron diffusion equation with a plane source is [see the attachment for equation] where [attached] is the neutron flux, [attached] is the plane source at x = 0, and D and K^2 are constants. a) Solve this equation by applying the Fourier transform. b) Transform your solution back into the x-space.

Smallest Value for E

An atomic particle is confined inside a rectangular box of sides a, b, c. The particle is described by a wave function that satisfies the Schrodinger wave equation [see the attachment] The wave function is required to vanish at each surface of the box (but not identically zero). This condition imposes constraints on the se ...continues

Transformation of Spatial Wave Functions and the momentum wave function of the ground state of the hydrogen atom

The hydrogen atom ground state may be described by the spatial wave function as: phi(r)= [(1/(Pi*(a_0^(3)))^(1/2)]*e^(-r/a0) This is where a_0 is the Bohr radius. Using the following equation, please calculate the momentum wave function. integral[(e^(-a*r + i*b*r))*(d^(3))*(r) = 8*Pi*a/((a^(2) + b^(2))^(2)) See the at ...continues

Heat Flow Equation

The heat flow in one dimension is governed by the partial differential equation [see the attachment for equation] where [attached] is the temperature in space as a function of time. Using the Fourier transform in x solve this equation given the condition [attached]; C is a constant.

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 ...continues

Propagation of sound in water

What are the minimum and maximum wavelengths of sound in water which are in audible range for a human ear? Assume an audible frequency range of 20 Hz to 20kHz, and speed of sound in water as 1500 m/s.

Finding the location where the total electric force on a given positive charge is zero in a region of two negative charges.

A charge of -3.50 nC and a charge of -6.30 nC are separated by a distance of 70.0 cm. Find the position at which a third charge of +7.40 nC can be placed so that the net electrostatic force on it is zero.

Gauss's Law.

I need to rewrite an equation for E-surface (electric field), with different variables (Lambda). Please see the attached file for the complete description. Thank you.

Calculating maximum power and efficiency

Can someone please tell me how I would calculate the maximum power and efficiency for this data set? I'm not sure if P=IV is appropriate and if it is I don't know how I would get Pmax.

Estimating the wt% Cu in Ni-Cu alloy Assuming that all magnetization comes from Ni electrons

A Ni-Cu alloy is prepared which has a lattice constant of 0.354 nm. The maximum magnetisation of the alloy is measured as 1.25*10^6 A/m. Assuming no interactions between Ni and Cu atoms, and the magnetisation comes from the all unpaired 3d Ni electrons.Estimate the wt. % Cu in the alloy. Both Ni and Cu have a fcc structure wit ...continues

Electric field/binomial expansion?

Show that, for points that are far from a hoop of charge q and radius r, the electric field looks like a point charge. Show this using a diagram and use binomial expansion. I'm not sure if I am setting this up correctly, and I really need help on the binomial expansion. Thank you.

Magnitude/Direction of Electric Field

Using the attached diagram, please help me with the following. (a) Find the magnitude/direction of the electric field at the center of the configuration of charges. (b) Using the result from (a), find the magnitude and direction of the force on an electron placed at the center of the configuration.

Interference of 2 Waves.

Two loudspeakers are placed side by side a distance d=4.00m apart. A listener observes maximum constructive interference while standing in front of the loudspeakers, equidistant from both of them. The distance from the listener to the point halfway between the speakers is l=5.00m. One of the loudspeakers is then moved dir ...continues

The beat detected on a moving platform

A speaker fixed to a moving platform moves to a wall, emitting a steady sound with a frequency of 250Hz. A person on the platform, right next to the speaker detects the sound waves reflected off the wall, and those emitted by the speaker. How fast should the platform move, vp, for the person to detect a beat frequency of 4.0 ...continues

Wave solutions of Maxwell's equations and Ampere-Maxwell law

An electromagnetic signal is generated by a Hertzian dipole located at a point P, which has the position vector r = ?(100m) ez. The signal is detected by a small wire loop located at the origin. Apart from the dipole and the loop, the nearby space is empty. Experimentation reveals that the detected signal is induced by a cha ...continues

Physics: An electron is accelerated by a potential difference of 75 V. What is its De Broglie Wavelength?

An electron is accelerated by a potential difference of 75 V. What is its De Broglie Wavelength?

Physics: If the stopping potential is 4.0 V What kinetic energy (eV) is given to the electrons by the incident light?

If the stopping potential is 4.0 V What kinetic energy (eV) is given to the electrons by the incident light?

Energy, Frequency, Wavelength

An electron in an excited Hydrogen atom drops from the second to first energy level. Calculate the energy, frequency and wavelength of the emitted photon.

Separation distance

Yellow-orange light from a sodium lamp of wavelength, 596 nm reaches two slits separated by 1.90 x 10^(-5) m. The screen is 0.60m away. What is the separation distance between the central max and the 1st order bright line?