Phys 4, Section 2                                                                     Jan 31, 2002

1. If work done in bringing a charge closer to another charge has the same sign
as the change in electric potential energy (i.e., W = )U), is the work referred to
being done by the electric system or by an external agent?
A) system             B) external agent             C) could be either

2. If a conductor is found to carry excess charge (under static conditions) the
charge must be
A) inside the conductor         B) on surface of conductor          C) either answer

3. Gauss’s law for electrostatics is just another form of
A) Newton’s Second Law         B) Ampere’s law              C) Coulomb’s law

4. Gauss’s law only applies to
A) open surfaces             B) closed surfaces                  C) either type

5. An electric field which falls off as 1/r is due to
A) point charge         B) line of charge              C) sheet of charge

6. Which of the following is a scalar field?
A) electric field             B) potential field             C) both             D) neither

7. What are correct units for electric potential (equivalent to volts)?
A) N·m             B) C/s             C) N/m             D) J/C             E) C²/m

8. The field due to a large flat charged sheet falls off proportional to
A) 1/r             B) 1/r²             C) doesn’t fall off

9. When a Gaussian cylinder of end cap area A = Br² and height h is centered
around a long line charge of linear charge density 8, the flux through an end 
cap is
A) k8A             B) k82Br              C) k8A/h                  D) 0

10. Which of the following symbols is used to refer to a surface charge density?
A) q                 B) D                  C) 8                  D) F

Answers: 1-b, 2-b, 3-c, 4-b, 5-b, 6-b, 7-d, 8-c, 9-d, 10-d

Last modified on February 07, 2002