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Electric & Magnetic Fields

Electric Field Problem

A proton is moving parallel to a uniform electric field. The electric field accelerates the proton and increases its linear momentum to 5.0 10-23 kg m/s from 1.5 10-23 kg m/s in a time of 6.0 10-6 s. What is the magnitude of the electric field?

Electric Potential

What is the electric potential at a distance 0.25 m away from a point charge of 1.0 x 10^-9 C? How much work is required to bring an identical charge from very far away up to this distance of 0.25 m from the first charge? Please show work with correct answer.

Magnetization problem.

Why do we need to take the derivative of Log(Z_N) with respect to beta when computing the magnetization?

Electric Fields

1. A point charge q produces an electric field of magnitude 90.5 N/C at a distance of 1.68 m. If the field is directed towards the charge, what is the value of q? 2. When the plates of a radio capacitor are charged with 0.18 mC, the potential between them is 9.0 V. What is the capacitance? 3. A pair of parallel plates is s

Calculate the electric field everywhere.

A spherically symmetric charge density occupies the region r<a. The charge density increases with radius as rho(r)=(rho,o)r^2 where rho,o is a constant. Calculate the electric field everywhere.

Electrical potential energy

Hi. Can someone please tell me if I've gotten the right answer to this problem? A computer monitor accelerates electrons and directs them to the screen in order to create an image. If the accelerating plates are 1.2 cm apart, and have a potential difference of 25,000 V, what is the magnitude of the uniform electric field betw

Inductance of a short coil

I have the inductance of the long coil which is L=( Meu (not)* N^2 * A ) / (D) A = Area , D = Length , N = number of turns in the coil I need to prove that for a short coil the inductance (L) is the following: L =[( Meu (not)* N^2 * A ) / (D)] * [ [{(D^2 - a^2)^(1/2)} - a ] / (D)] ] a = radius of the coil A = 3.14 a^

Dipole and work

How much work is done moving a unit positive charge form 1 point of a triangle to another in the field of a dipole p? The triangle has the angles 45,45,90 with a base of length a. The dipole is located at the right base corner pointing in the -x direction. The positive unit charge has to be moved from the left corner to the t

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.

Answers in AmE2 and Nm

A circular coil of wire has a radius of 0.14 m. The coil has 80 turns and a current of 15 A, and is placed in a magnetic field whose magnitude is 0.30T. Determine the moment and maximum torque it can experience.

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

Physics: Draw the path of a proton; find the change in direction

A proton enters a region where the electric field has a magnitude of 500 N/C and is produced by two charged plates. The length of the plates is .200M. The initial velocity is 3X10^6 m/s in the postive x direction. A) Draw the path of the proton. B) Find the change in the y direction of the proton.

Parallel Plates

According to section E3.4, the electric field E between two parallel plates with opposite, uniformly distributed charges is ( as long as the plates are very large compared to their seperation d) nearly uniform and has magnitude E= 4(pi)k(sigma), where sigma is the charge per unit area on the plates. Use this result to verify th

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