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Electric & Magnetic Fields

Magnetic field and current-carrying wires

Figure shows, in cross section, four thin wires that are parallel, straight, and very long. They carry identical currents, in the directions indicated. Initially all four wires are at distance d = 17.5 cm from the origin of the coordinate system, where they create a net magnetic field B. (a) To what value of x must you move


1. A nonconducting sphere has radius R=2.31cm and uniformly distributed charge q = +3.50fC. Take the electric potential at the sphere's center to be Vo = 0. What is V at radial distance (a) r =1.45cm and (b) r = R. ( answer is given as (a) is -0.268mV (b) -0.681mV, please show me the detail, thank you) 2. Two particles,

Physics question

The question is in the attached file, it's a page of text book. Please help me to do QUESTION NUMBER 50. Only question 50. 50. Figure 23-51 shows a spherical shell with uniform volume charge density rho = 1.84 nC/m3, inner radius a = 10.0 cm, and out radius b = 2.00a. What is the magnitude of the electric field at radial

Two problems on electrostatics

1. Two charged concentric spherical shells have radii 10.0cm and 15.0cm. The charge on the inner shell is 4.00X10^-8C, and that on the outer shell is 2.00X10^-8C. Find the electric field (a) at r = 12.0cm and (b) at r = 20.0cm. 2, Two Large metal plates of area 1.0 m^2 face each other. They are 5.0 cm apart and have equal but

Electric Fields

A 43.2 nC Charge is located at position (x,y) = (1.0 cm, 2.0 cm). At what position (x,y) position is the electric field 1) At -225,000i N/C? 2) At (161,000i + 80,500j) N/C X=? Y=? 3) At (21,000i - 28,800j) N/C X=? Y=?

Charged surfaces.

Two charged, parallel, flat conducting surfaces are spaced d = 1.4 cm apart and produce a potential difference of 655 V between them. An electron is projected from one surface directly toward the second. What is the initial speed of the electron if its comes to rest just at the second surface? This is what I've been trying t

Magnetic Field due to a Current.

The problem states: Two semicircular arcs have radii R2 = 7.80 cm and R1 = 3.15 cm, carry current i = 0.281 A, and share the same center of curvature C. What are the (a) magnitude and (b) direction (into or out of the page) of the net magnetic field?

Electrostatic Charges & Fields

Problem 13 :- In figure 21-26 in attached file 3 particle 1 of charge +1.0 uC and particle 2 of charge -3.0 uC are held at separation L = 10.0cm on an x axis. If particle 3 of unknown charge (q3) is to be located such that the net electrostatic force on it from particles1 and 2 is zero. What must be the (a)x axis and (b) y

Force between current carrying conductors.

The following figures (attached) show parallel cables and the orientation of their currents. Indicate the direction of the force that each cable has and the orientation of the magnetic fields.

Two concentric circular loops each have currents of 2.5 x 10^-3 amperes with radii of 10 cm and 4 cm. The currents travel in opposite directions for each loop. How would you calculate and draw the magnetic field at the common center, and in what direction would the field be pointing in?

Two concentric circular loops each have currents of 2.5 x 10^-3 amperes with radii of 10 cm and 4 cm. The currents travel in opposite directions for each loop. How would you calculate and draw the magnetic field at the common center, and in what direction would the field be pointing in?

What is the average current that flows through the coil during this time?

A circular coil enclosing an area of 100 cm^2 is made of 200 turns of copper wire. The wire making up the coil has a resistance of 5.0 ohms, and the ends of the wire are connected to form a closed loop. Initially, a 1.1 Tesla uniform magnetic field points perpendicularly upward through the plane of the coil. The direction of t

Charges: What are the values of the distance l and the charge q?

Two charges, each with a value of +q are separated by a distance of l m. The resultant electric field and the potential measured at a point P a distance l/3 m from the left charge, are, 10 N/C and 2 V, respectively. What are the values of the distance l and the charge q?

Electric field due to a charged disc

A uniformly charged disk of radius 35.0 cm carries charge with a density of 7.90 x 10^-3 C/m^2. Calculate the electric field on the axis of the disk at (a) 5.0 cm, (b) 10.0 cm, (c) 50 cm and (d) 200 cm from the center of the disk.

Magnetic Fields Produced by Currents

Two rigid rods are oriented parallel to each other and to the ground. The rods carry the same current in the same direction. The length of each rod is 0.85 m, while the mass of each is 0.073 kg. One rod is held in place above the ground, and the other floats beneath it at a distance of 8.2 x 10^-3 m. What is the current in the r

Source of Magnetic Field

A tightly wound solenoid 20 cm long has 400 turns and carries a current of 4A so that its axial field is in the z direction. Neglecting end effects, find B and Bsubapp at the center when (a) there is no core in the solenoid and (b) there is an iron core with a magnetization M=1.2 x 10 ^6A/m.

Source of Magnetic Fields

A very long coaxial cable consists of an inner wire and a concentric outer cylindrical conducting shell of radius R. At one end, the wire is connected to the shell. At the other end, the wire and shell are connected to opposite terminals of the battery, so there is s current down the wire and back up the shell. Assume that the c

Source of Magnetic Field

A solenoid with length 30 cm, radius 1.2 cm, and 300 turns carries a current of 2.6 A. Find B on the axis of the solenoid (a) at the center, (b) inside the solenoid at a point 10 cm from one end, and (c) at one end,

Source of the Magnetic Field

A single-turn circular loop of radius 3 cm carries a current of 2.6 A. what is the magnitude of B on the axis of the loop at (a) the center of the loop, (b) 1 cm from the center, (c) 2 cm from the center, and (d) 35 cm from the center?

Electric Field and Stored Energy of Parallel-Plate Capacitor

A parallel-plate capacitor with plate area of 2 m^2 and a separation of 1.0 mm is charged to 100 V. (a) What is the electric field between the plates? (b) what is the energy per unit volume in the space between the plates? (c) find the total energy by multiplying your answer from part (b) by the total volume between the

Electric field lines & equipotential lines

Draw a picture of the electric field lines generated by a collection of two positive charges, both of charge q = 1. Center one at (1,0) and the other rat (-1,0). What happens to the electric field at the origin? (the point 0,0) Draw a few equipotential lines. Remember, these are the curves that circle the charge distribut

Equipotential Surfaces

The electric field has a constant value of 4.0 x 10^3 V/m and is directed downward. The field is the same everywhere. The potential at a point P within this region is 155 V. What is the potential at a point (a.) 6.0 x 10^-3 m directly above P, (b.)3.0 x 10^-3 m directly below P, and (c) 8.0 . 10 ^-3 m directly to the right of

Solve: Electric Potential Difference

Question: Two protons are moving directly towards one another. When they are very far apart, their initial speeds are 3.00 x 10^6 m/s. What is the distance of closest approach?

Diagrams of Electric Fields

Draw electric field lines for a quadrupole formed of charges +Q, -Q, +Q, -Q at the corners of a square. Charges on a diagonal have the same sign. (On a field line, dy/dx = Ey/Ex)

Determining velocity of a proton accelerated by an electric field.

A proton is accelerated from rest by an electric field. The electric field starting point's potential is zero but the ending point electrostatic potential is -5,000 volts. I need to determine how to find the velocity of the proton at the ending point of 9.78 x 10^5 meters/second.

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