1. What is electric charge? What is an electric field? Draw the electric field for the
following charge configurations:
(a) a positive charge (b) a negative charge (c) a positive and a negative charge
(d) two positive charges (e) two negative charges
2. A solid sphere of radius a is concentric with a hollow sphere of radius b, where b>a.
The solid sphere has a charge +3Q and the hollow sphere has a charge of -2Q.
Find the electric field at r:
(a) For a<r<b.
(b) For r>b.
3. In a certain crystal, Cl- atoms form the 4 corners of a triangular pyramid, separated
from one another by 50nm. Find the electric field in the middle of the pyramid.
4. Use Gauss’ Law to find the electric field of the following charge distributions and
answer the following questions. Give the electric field for all regions of space.
(a) a point charge
(b) a solid sphere of uniform charge density
(c) a hollow sphere with uniform charge density
(d) a line of charge
(e) an infinite sheet of charge
(f) a conducting surface
(g) compare the electric fields of a point charge, a line charge, and a sheet of charge.
5. What would be the electrical field required to keep an electron in a stable circular orbit
in a Hydrogen atom?
6. A small sphere is placed midway between the plates of a parallel plate capacitor.
(separation distance between the plates is 40 cm, negative plate on the bottom)
(a) Sketch the electric field lines between the plates.
(b) If the plates are maintained at 50kV, what is the magnitude of the electric field
between the plates?
(c) If the sphere has a mass of 2 grams, what must be the charge of the sphere for it to
remain stationary in the middle?
(d) How many electrons would correspond to your answer in (c)?
7. A muon is decelerated by an electric field of 2.2 x 103 N/C to rest over a distance of
4.20cm.
(a) Find the particle’s initial velocity and kinetic energy.
(b) Perform the same calculations in (a) for a tau particle
8. Discuss the history of electromagnetism in detail.
Answer all questions thoroughly please
