Name: _ Recitation Section: _
Spring 2016 Physics 2140 Quiz 1
1. Two electrons (e1 and e2) and a proton (p) lie on a straight line, as shown. The directions of
the force of e2 on e1, the force of p on e1, and the total force on e1, respectively, are:
A) ,
Where does electric charge come from?
Atoms = protons + neutrons + electrons.
p
Atoms are NEUTRAL
Method of charging:
g g
a. by friction;
b.
b by contact;
c. by induction.
How much charge in a penny?
Mass of a penny of copper: m = 3.11g.
(1) Atoms it
Gravitational Field: How does the pencil know where to go?
Gravitational Field Line
Pencil
Ground
The trajectory of the pencil is the gravitational field line.
Electric Field: How does a positive testing charge know where to go?
q0
q0
+

Electric Field b
Phys2140: Quiz #2
Name:_ ID (Last 4digit):_ Session:_
Part I: Multiple choice questions, one point each, no partial credit.
Please circle your answer.
k = 9x109 Nm2/C2
1. The diagram shows the electric field lines in a region of space containing two smal
How to calculate the electric field due to
electric charges arranged in common shapes?
l ti h
di
h
?
Gauss Law relates
the electric fields at
points on a closed
Gaussian surface and
the net charge enclosed
by the surface.
The direction of a surface: The d
Phy52140: Quiz #3
Name: ID {Last 4digit): Session:
Part I: Multiple choice questions, one point each, no partial credit.
Please circle your answer. k = 9x109 NmZIC2
l. The flux ofthe electric ﬁeld (24 NC)? + (30 N/C)j + (16 N/C) 12 through a 2.01112 po
Quiz #4
Sunday, February 7, 2016
5:13 AM
Phys2140: Quiz #4
Name:_ ID (Last 4digit):_ Session:_
Part I: Multiple choice questions, one point each, no partial credit.
k = 9x10 9 Nm2/C2
Please circle your answer.
1. A particle with a charge of 5.5 106 C is