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Electric & Magnetic Fields

Electric Field & Magnitudes

The lines show the equipotential contours in the plane of three point charges, Q1, Q2, and Q3. The values of the potentials are in kV as indicated for the +5, 0, and -5 kV contours. The positions of the charges are indicated by the dots. the work required to move a charge of -0.51×10-12C from i to b is 3.06×10-9 J a: Ca

Expression Point Charges

y l l a (+q) l l -------l--------x l -a (+2q) l l Two point charges are fixed on the y-axis at the locations shown in the figure above. A charge of +q is located at y = a and a charge of +2q is located at y = -a. Express your answers to a an

Impossible electrostatic field, charges and work

See attached file for full problem description. 8. (a) Three charges are situated at the corners of a square (side a) as shown in Figure 2.41: (a) how much work does it take to bring in another charge, +q, from far away and place it in the fourth corner? (b) How much work does it take to assemble the whole configuration of

Vector Functions

See attached file for full problem description. Only problems # 3 and #4.

Electric Field, Radioactivity & X-Ray Wavelength

1. The drawing shows the potential at five points on a set of axes. Each of the four points is 7.0 x 10^-3 mt from the point of origin. From the data shown find the magnitude and the direction of electric field in the vicinity of origin. (See attached for diagram) 2. A 0.5 kg tumor is being irradiated by a radioactive sou

Electric Forces and Fields

An electrically neutral model airplane is flying in a horizontal circle on a 3.0-m guideline, which is nearly parallel to the ground. The line breaks when the kinetic energy of the plane is 50.0J. Reconsider the same situation, except that now there is a point charge of +q on the plane and a point charge -q at the other end of t

Quadruple Magnetic Fields

(See attached file for full problem description) (a) The arrangement of magnets attached is called a quadrupole. Sketch the magnetic field lines around the two magnets. At what point would the magnetic forces cancel out? (b) Sketch also the field lines in this arrangement and mark where the forces cancel out.

Parallel plates capacitor

Two parallel plates are .005m apart and are each 2m2 in area. The plates are in vacuum and an electric potential difference of 10,000V is applied across them. 1) Find the: a)capacitance, b)the charge on each plate c)the electric field intensity in the space between, and d) the stored energy. 2) If a dielectric mater


See attached file for full problem description. Three point charges are located along the circle of radius. Derive the expression for the electric field in the center.

Electromagnetic Waves and Electric Fields

Suppose a plane electromagnetic wave has a wavelength of 50 m and the electric field vibrates with an amplitude of 22 V/m. Calculate the frequency of the wave, the amplitude of B. Write an expression for B in a the form B=Bo cos(kx-w(omega)t) with numerical values for B0, k, and w. See attachment for better formula representatio

Force on a current carrying conductor due to magnetic field.

In this problem i am not sure if you can just use the right hand screw rule The cube is 40 cm on each edge. Four straight segments of wire - ab, bc, cd, and da - form a closed loop that carries a current I = 5 A, in the direction shown. The loop is placed in a uniform magnetic field of magnitude B = 0.020 T in the positive y

Electric Fields of Charge Distributions

Two protons are 3.6 nm apart. Find the magnitude of the electric field (a) 4.8 nm and (b) 200 nm to the right of the right-hand proton in the figure above. (c) Show that your answer to (b) in nearly equal to the field of a single charge 2e located midway between the two protons. (see attached diagram)

Mutual inductance and inductance of a transformer primary

1) How would you arrange two flat circular coils so that their mutual inductance was a) greatest b) least (without separating them by a great distance)? 2) If you are given a wire of such length that you can make only two loops out of it, how would you shape this wire to obtain a) the greatest; b) the least self-inductance?

Uniform Charge Density

A long cylindrical beam (with circular cross section) of charged particles has velocity v in the axial direction. The beam has a uniform charge density p f (assume fixed). Find B inside and outside the beam as a function of distance from the axis, in terms of given quantities.

Magnetic field at the core of a solenoid

A solenoid that is 75 cm long produces a magnetic field of 2.1 T within its core when it carries a current of 6.8 A. How many turns of wire are contained in this solenoid?


1) If the cathode and anode are 0.4cm apart calculate the electric field 2) What is the force on an electron in this field? 3) What is the acceleration of an electron in this field? 4) What is the velocity of this electron when it reaches the anode? 5) Are relativistic affects likely to make your calculation imprecis

Magnitude of force

(Refer to attached picture file) An electron moving 6.00x105 m/s in the x-z plane at an angle of 60o as shown is at the origin of a Cartesian coordinate system. The magnetic field B is 2.00 T in the positive x direction. Find the magnitude of the force on the electron and state its direction in reference to the x, y, and z ax

Electromagnetism: Force on moving charge in a magnetic field

1. In an experiment with cosmic rays, a vertical beam of particle that have charge of magnitude 3e and mass 12 times the proton mass enters a uniform horizontal magnetic field at 0.250 T and is bent in a semicircle of diameter 95.0 cm a) Find the speed of the particles and the sign of their charge. b) Is it reasonable to ignor

Electric field of three charges

Refer to three charges shown & arranged in attached picture file: What is the magnitude and direction of the force on the - 3.25 mC charge? What is the magnitude and direction of the electric field at point x? See attached file for full problem description.

Electrical Field Problem

See Attached .jpg for further information on this as well, please: Three charges of equal magnitude q are fixed in position at the vertices of an equilateral triangle (drawing). A fourth charge Q is free to move along the positive x axis under the influence of the forces exerted by the three fixed charges. Find a val

Consider an extended one-dimensional rod of length L and charge Q uniformly distributed. Determine the field from the rod at a point P a distance y from its center perpendicular to the rod.

I'm taking the E&M Class of a first-year Physics with Calculus series. We're working with determining the electric fields of extended objects with integration, and I'm having trouble with properly modeling the problems. If someone could show me a sample solution to one of these, I feel it could really help. Here goes: Consi

Magnitude of The Net Electric Field

I need some help determining variables in an electric field: (see attached file for diagram) - setup of each particle - magnitude on point P - in the magnitude setup, how to setup the r^2 in the equation for each Q particle, and how to add them all together.

Voltage Due to Charge Configuration

Let a uniform surface charge density of 5 nc/m2 be present at the z=0 plane, a uniform line charge density of 8 nc/m, be located at x=0, z=4 and a point charge of 2 μC be present at P(2,0,0). If V=0 at M(0,0,5), find V at N(1,2,3). It seems to me that I need to find the electric field intensity for each of the charge configur