Questions from Electronics

Q: (a) Carry through the argument in Sect. 8.

(a) Carry through the argument in Sect. 8.1.2, starting with Eq. 8.6, but using J f in place of J. Show that the Poynting vector becomes S = E × H, (8.46) and the rate of change of the en...

Q: A circular disk of radius R and mass M carries n point

A circular disk of radius R and mass M carries n point charges (q), attached at regular intervals around its rim. At time t=0 the disk lies in the xy plane, with its center at the origin, and is rotat...

Q: Calculate the force of magnetic attraction between the northern and southern hemispheres

Calculate the force of magnetic attraction between the northern and southern hemispheres of a uniformly charged spinning spherical shell, with radius R, angular velocity ω, and surface charge density...

Q: Use the cross product to find the components of the unit vector

Use the cross product to find the components of the unit vector n perpendicular to the shaded plane in Fig. 1.11.

Q: Compute the divergence of the function v = (r cos

Compute the divergence of the function v = (r cos θ) rˆ + (r sin θ) θˆ + (r sin θ cos φ) φˆ....

Q: (a) Consider two equal point charges q, separated by

(a) Consider two equal point charges q, separated by a distance 2a. Construct the plane equidistant from the two charges. By integrating Maxwell’s stress tensor over this plane, determine the force of...

Q: Imagine two parallel infinite sheets, carrying uniform surface charge σ (

Imagine two parallel infinite sheets, carrying uniform surface charge σ (on the sheet at z =d) and -σ (at z=0). They are moving in the y direction at constant speed v (as in Problem 5.17). (a) What is...

Q: A charged parallel-plate capacitor (with uniform electric field

A charged parallel-plate capacitor (with uniform electric field E = E zˆ) is placed in a uniform magnetic field B = B xˆ, as shown in Fig. 8.6. (a) Find the electromagnetic momen...

Q: Consider an infinite parallel-plate capacitor, with the lower plate

Consider an infinite parallel-plate capacitor, with the lower plate (at z = −d/2) carrying surface charge density −σ , and the upper plate...

Q: In Ex. 8.4, suppose that instead of turning

In Ex. 8.4, suppose that instead of turning off the magnetic field (by reducing I ) we turn off the electric field, by connecting a weakly10 conducting radial spoke between the cylinders. (We’ll have to...