Electricity and Magnetism Answers

Three infinitely large, parallel, insulating planes of charge are arranged. The planes from left to right have the following charge densities: -3σ, +2σ, and + σ. The distances between the planes are indicated. Since there are 3 planes, there are a total of 4 regions. Zones 1, 2, 3 and 4 respectively. Consider the regions 1 and 4. How does the electric field magnitudes in these regions compare?

12 infinite lines of charge each with -λ are equally spaced and fixed around a circle of radius R. A proton (of charge +e) is located at the center of the circle. Now, the line charge at the 6 o'clock position is removed from the charge configuration leaving the others fixed. What is the magnitude of the net force on the proton?

Consider the configuration of three point charges (all having the same charge) forming a equilateral triangle (all sides have length a) in the x-y plane. Assume that all three charges are released from rest at the same time. When the charges are far away from each other. What is their total kinetic energy ?

The wavelength of the green laser of the light effect device is 531 nm.

What is the frequency of such light?

A thin disc of outer radius b with a concentric hole of radius a carries a current given by surface current density K = Ko0 around its z axis. 

(a) Find the total current I. (b) Find the magnetic field g (magnitude and direction) at the center of the disk. (c) Find the magnetic dipole moment m of the disk. 

two electrostatic point charges of +60.0 μc and +50.0 μc exert a repulsive force on each other of 175 n. what is the distance between the two charges?