Chapter 4.1, Problem 4.9P

Repeat the previous problem, assuming that the electric field is directed along a body diagonal of the cube.

Calculate the electric field due to a uniformly charged rod of length L, aligned with the x-axis with one end at the origin; at a point P on the z-axis.

Check Your Understanding What is the electric field due to a single point particle?

Recall that in the example of a uniform charged sphere, p0=Q/(43R3). Rewrite the answers in terms of the total charge Q on the sphere.

Calculate the angular velocity of an electron orbiting a proton in the hydrogen atom, given the radius of the orbit is 0.5301010 m. You may assume that the proton is stationary and the centripetal force is supplied by Coulomb attraction.

Suppose a speck of dust in an electrostatic precipitator has 1.00001012 protons in it and has a net charge of 5.00 nC (a very large charge for a small speck). How many electrons does it have?

A thin conducting plate 1.0 m on the side is given a charge of 2.0106C . An electron is placed 1.0 cm above the center of the plate. What is the acceleration of the electron?

A long copper cylindrical shell of inner radius 2 cm and outer radius 3 cm surrounds concentrically a charged long aluminum rod of radius 1 cm with a charge density of 4 pC/m. All charges on the aluminum rod reside at its surface. The inner surface of the copper shell has exactly charge to that of the aluminum rod while the outer surface of the copper shell has the same charge as the aluminum rod. Find the magnitude and direction of the electric field at points that are at the following distances from the center of the aluminum rod: (a) 0.5 cm, (b) 1.5 cm, (c) 2.5 cm, (d) 3.5 cm, and (e) 7 cm.

Determine if approximate cylindrical symmetry holds for the following situations. State why or why not. (a) A 300-cm long copper rod of radius 1 cm is charged with +500 nC of charge and we seek electric field at a point 5 cm from the center of the rod. (b) A 10-cm long copper of radius 1 cm is charged with +500 nC of charge and we seek electric field at a point 5 cm from the center of the rod. (c) A 150-cm wooden rod is glued to a 150-cm plastic rod to make a 300 cm long rod, which is then painted with a charged paint so that one obtains a uniform charge density. The radius of each rod is 1 cm, and we seek an electric field at a point that is 4 cm from the center of the rod. (d) Same rod as (c), but we seek electric field at a point that is 500 cm from the center of the rod.