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Electric & Magnetic Fields

Electric field due to seven point charges

Consider a cube of edge a with the location and orientation of the fig. (see attachment). There is a point charge q at each corner except at (a,a,0). Find E at the empty corner.

Set of four problems on elecrostatics.

1) A charge +2q is placed at the origin and a second charge -q is placed at x = 3.0 cm. Where can a third charge +Q be placed so that it experiences a zero force? 2) A charge of -4.00 micro C is fixed in place. From horizontal distance of 55.0 cm, a particle of mass 2.50*10^-3kg and charge -3.00 micro C is fired

A wall has a negative charge distribution producing a uniform horizontal electric field. A small plastic ball of mass 0.01 kg, carrying a charge of -80.0 µC, is suspended by an uncharged, nonconducting thread 0.30 m long. The thread is attached to the wall and the ball hangs in equilibrium (as show in the attachment)in the elastic and gravitational fields. The electric force on the ball has a magnitude of 0.032 N. Answer the following four questions.

A wall has a negative charge distribution producing a uniform horizontal electric field. A small plastic ball of mass 0.01 kg, carrying a charge of -80.0 µC, is suspended by an uncharged, nonconducting thread 0.30 m long. The thread is attached to the wall and the ball hangs in equilibrium (as show in the attachment)in the ela

Force in an electric field.

A positive test charge of 9.0E-5 C is placed in an electric field of 35.0 N/C intensity. What is the strength of the force exerted on the test charge?

current carrying wire in magnetic field

5. A current flows in a wire in direction 3i+4j where the direction of the magnetic field is 5i+12k. The direction of force on the wire is? 6. A current I flows in a straight wire of length L at an angle of 30 degrees from the direction of a magnetic field B. the force on this wire is? 7. If the voltage on a capacitor is doubl

Infinitely long line of charge

An infinitely long line of charge has linear charge density 4.50×10^-12 Coulombs/m. A proton (mass 1.67×10^-27 kg, charge 1.60×10^-19 C) is 12.5 cm from the line and moving directly toward the line at 3000 m/s. 1) Calculate the proton's initial kinetic energy in J. 2) How close, in metres, does the proton get to the line

Electric Field Between 2 Plates

A uniform, upward-directed electric field E of magnitude 2.00 x10^3 N/C has been set up between two horizontal plates by charging the lower plate positively and the upper plate negatively. The plates have length L=0.1m and separation d=0.02m. An electron is then shot between the plates from the left edge of the lower plate. The

Electric Fields on a Circular Disk

A circular disk has a charge density 0f G C/m^2 and a radius of R m. A test charge, P, is located Z m above the center of the disk on a line perpendicular to the disk and passing through the center of the disk. Using polar coordinates (d(area) = r*dr*d(theta)) find the value of the electric field ,E, at P.

Equipotential Surfaces in an Electric Field

See the attached file. The dashed lines in the diagram represent cross sections of equipotential surfaces drawn in 1-V increments. a) What is the work W_AB in J done by the electric force to move a 1-C charge from A to B? b) What is the work W_AD in J done by the electric force to move a 1-rm C charge from A to D? c)

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

Electrostatics - Nonconducting Spheres

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,

The electric field between two charged disk

Two 10-cm-diameter charged disks face each other, 20 cm apart. The left disk is charged to - 50nC and the right disk is charged to + 50nC. a) What is the magnitude of the electric field vector in N/C at the midpoint between the two disks? b) What is the magnitude of the force F vector in N on a - 1.0nC charge placed at the m

E-field of a spherical shell with uniform volume charge

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

Determining Ratio of Stored Energy: Example Problem

A slab of copper of thickness b = 1.167 mm is thrust into a parallel plate capacitor of C = 2.00×10-11 F of gap d = 7.0 mm, as shown in the figure (image attached); it is centered exactly halfway between the plates. What is the capacitance after the slab is introduced? If a charge q = 4.00×10-6 C is maintained on the plates,

Gaussian Surface around the Room Air Volume Charge

When a shower is turned on in a closed bathroom, the splashing of the water on the bare tub can fill the room's air with negatively charged ions and produce an electric field in the air as great as 1000N/C.Consider a bathroom with dimensions 2.5m X 3.0m X2.0m. Along the ceiling, floor, and four walls, approximate the electric fi

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=?

Distance, acceleration, collision, force, strength of electric

1) The average distance an electron travels between collisions is 2.0 um. What acceleration must an electron have to gain 2.0 * 10^{ - 18} J of kinetic energy in this distance? 2) What force must act on the electron to give it that acceleration? 3) What strength electric field N/C will exert this much force on an electron?

Calculating Magnitude and Direction of Electric Field

The electric potential V in the space between two flat parallel plates is given by V = 1300x^2 , where V is in volts if x, the distance from one of the plates, is in meters. Calculate the magnitude and direction of the electric field at x = 2.90 cm. What is the x-component of E?

deceleration of an electron in an electric field

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

Determining electric field after spherical cavity is cut

A positive charge Q = 1600.00 C is uniformly distributed over the volume of a sphere of radius R = 5.00 m. Suppose a spherical cavity of radius R/2 is cut out of the solid sphere, the center of the cavity being a distance R/2 from the center of the original solid sphere (image attached). The cut-out material and its charge

Magnitude of the electric field with distribution of charges

A. Calculate the magnitude of the electric field at the origin due to the following distribution of charges: +q at (x,y) = (a,a), +q at (a,-a), -q at (-a,-a) and -q at (-a,a). Where q = 2.25*10^-7C and a = 8.85 cm. B. (view image attached) Set up an 8-point compass at the origin, where north points along the positive y-axis,

Electrostatics: Distance of Points Along the Axis

The E-Field at the center of a ring of charge is zero. At very large distances along the axis the E-field goes to zero. Find the distance of the points along the axis at which the E-field is a maximum. The radius of the ring is 5 cm and the total charge on the ring is .33 C.

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?

Synchrotron for fixed target collisions

To achieve an energy of 20TeV, each of the SSC main rings contains approximately 4000 dipole magnets, each 16m long with a field of 7T. This means that over half of the 60mile SSC tunnel is taken up by dipoles. if you were to build a single synchrotron for use in fixed-target collisions of equivalent energy in the center-of-ma