Electricity and Magnetism Answers

Consider an infinite surface charge in y-z plane with density σ. Electric field at any point in positive x-axis is σ/2ϵ (i hat) and electric field at any point in negative x-axis is -σ/2ϵ (i hat). Thus we see there is a discontinuity of σ/ϵ at the surface (at x=0). What will be the electric field on the surface charge? That is, what will be the electric field at x=0?

A uniform plane wave of 10 kHz travelling in free space strikes a large block of a material having ε=9ε_0,μ=4μ_0 and σ=0 normal to the surface.If the incident magnetic field vector is given by B→=10^(-3) sin(ωt-βy)k^ tesla
Write the complete expression for the incident,reflected and transmitted field vectors.
Please explain in detail.

A uniform plane wave of 10 kHz travelling in free space strikes a large block of a material having ε=9ε_0,μ=4μ_0 and σ=0 normal to the surface.If the incident magnetic field vector is given by B→=10^(-3) sin(ωt-βy)k^ tesla
Write the complete expression for the incident,reflected and transmitted field vectors.

A dipole with a dipole moment of strength p= 5.64*10^-4 Cm is located D= 0.71 m away from a grounded plane conducting surface. The direction of the dipole moment is perpendicular to the conducting surface. Calculate the strength of the translational force on the dipole with positive values indicating a force away from the surface and negative values a force toward the surface. The displace between the charges forming the dipole is much smaller than the distance of the dipole from the surface.

A thread charged homogeneously with line density λ=3.47 μC/m forms a loop in the shape of a cut circle with radius r=6.12m, cut by a line parallel to the y-axis with length l=10.54. Calculate the elctric field at the center of the circle. State direction and magnitude of the electric field vector.

Three point charges are arranged along the x-axis. Charge q1 = +3.00 µC is at the origin, and charge q2 = - 5.00 µC is at x = 0.200 m. Charge q3 = - 8.00 µC. Where is q3 located if the net force on q1 is 7.00 N in the – x-direction?

Three point charges of 3µC, 8µC and 5µC are located at the corners of an equilateral triangle of side 0.4m, calculate the net force on the 8µC?

Calculate the columb force (F1), between two equal charges placed in vacuum separated at a distance square of r meters apart. By what factor does F1 changes when the separation is doubled?

A group of students are recreating Millikan’s Oil Drop experiment in which a charged oil droplet is suspended in the electric field created by two horizontal charged plates. The droplet experiences a downward force due to gravity and an upward force due to the electrostatic force from the charges. The forces are balanced so that the droplet does not accelerate. In this case, the two horizontal parallel plates are 0.80 cm apart. A sphere of mass 2.73 x 10–13 kg remains stationary when the potential difference between the plates is 315 V with the upper plate negative.
Draw the FBD of the oil droplet.
Is the sphere positively or negatively charged? Explain how you know.
Calculate the magnitude of charge on the sphere.
How much excess or deficit of electrons does the sphere have?

Three point charges A, B, and C sit on the corners of an equilateral triangle with side length 10cm. Each charge has a of magnitude 2.32 x 10-6 C with charge A and C being negative and B being positive, as shown in the diagram below. What is the net force on each of the point charges? Include vector diagrams for each charge in your answer.