Explore BrainMass

Electric & Magnetic Fields

Perturbation Theory with Atoms

See attachment for better symbol representation. When an atom is placed in a uniform external electric field Eext, the energy levels are shifted - a phenomenon known as the stark effect. In this problem we analyze the stark effect for the n=1 and n=2 states of hydrogen. Let the field point in the z direction, so the potent

Magnetic Force

A wire 2.80 m in length carries a current of 5.00 A in a region where a uniform magnetic field has a magnitude of 0.390 T. Calculate the magnitude of the magnetic force on the wire assuming the angle between the magnetic field and the current is (a) 60.0, (b) 90.0, (c) 120.

Magnetic Field Strength

A piece of copper wire has a resistance per unit length of 6.45E-3 omega/m. The wire is wound into a thin, flat coil of many turns that has a radius of 0.170 m. The ends of the wire are connected to a 12.0 V battery. Find the magnetic field strength at the center of the coil. Answer in T.

Question about Potential Difference

A uniform electric field of magnitude 250 V/m is directed in the positive x direction. A +12.0 micro coloumb charge moves from the origin to the point (x, y) = (20.0 cm, 50.0 cm). a) What is the change in the potential energy of the charge-field system? b) Through what potential difference does the charge move?

Physics - Electric Field

Electric Field Four identical point charges (q = + 10.0 micro coulomb) are located on the corners of a rectangle. The dimensions of the rectangle are L = 60.0 cm and W = 15.0 cm. Calculate the magnitude and direction of the resultant electric force exerted on the charge at the lower left corner by the other three charges.

Electric Force

Three charges are placed on the x and y axes as follows:+2q at the origin (0,0); -q at (a,0); +q at (0,a). Find the magnitude and direction of the electric field at the point (a/2,a/2), mid-way between the +q and -q charges.

Solenoid Problem

A Solenoid has 704 turns, a length of 33.3 cm, a radius of 3.85 cm. If it carries 5.61 A, calculate the magnetic field at an axial point located 20.2 cm from the center. Answer in units of T.

Parallel plate capacitor: Physical arrangement of plates

Imagine that you would like to design a parallel plate capacitor that could store 1 J of electrical energy in the electric field between its plates when connected to a 1.5 V battery. Imagine that you can arrange things so that the plates can be separated by a distance d as small as 0.5 mm. (Hint argue that the electric field st

Calculate the capacitance of the coaxial cable arrangement for an electric field

See attached file for clarity. The electric field outside a uniformly charged, infinite cylindrical conductor is the same as if the cylinder's charge were concentrated in a thin wire along the cylinders axis. Moreover, the potential inside a uniformly charged infinite cylindrical pipe like that inside a spherical shell is co

Electric field vectors for two circular parallel plates

See attached file for clarity. Consider two circular parallel plates of radius R separated by a distance d  R. Assume that these plates have uniformly distributed surface charges of Q and -Q. Electric field vectors in the region between the plates will all point perpendicular to the plates from the positive

binomial approximation for a three dimensional potential field

Consider a dipole consisting of two charged particles on the x axis, one with positive charge q+ located at x=+1/2d and one with negative q- charge located at x=-1/2d a) Derive an exact expression for the three dimensional potential field created by this dipole at a point P whose coordinates are {x, y, and z} b) Use the bi

Electric and potential fields...(solid conducting core)

Consider a concentric spherical system made up of the following parts: A solid conducting core radius a with total charge Qc , surrounded by a conducting shell of inner radius b and outer radius c. The shell has total charge -Qc . For each of the appropriate regions, find Qenclosed , E and V. Make the appropriate set of gr

Compute the direction and magnitude of the electric field.

In Figure A1 in the attachment, the boundary between two ideal dielectrics is shown. Near the boundary, on Er1 side, the electric field is measured and found to be perpendicular to the boundary and equal to 100 V/m. a) What is the direction of the electric field E, near that boundary and on Er2 side? b) What is the magnitu