Known Errors in the Second Printing of Unit
E, 1/e
NOTE:
In all that follows I will use <letter name> to
represent a Greek-letter variable, ^ to indicate that the next
quantity is superscripted, _ to indicate that the next quantity is
subscripted, and boldface to indicate a vector quantity. I will also
go against typographical convention and put punctuation
outside of quotation marks to make whatever is enclosed in
quotes exactly reflect what is (or should be) in the
text.
Error notices added most recently (1/23/99 and 2/9/99) are marked
in red.
- Table of Contents: "E7 Analyzing
Circuits" should be "E7 Capacitors and Energy".
- page xiv, second line before section 6:
"about how design" should be "about how to design".
- page xv, second line of section 8:
"snapshot of work" should be "snapshot of a work".
- page 23, beginning of the last line in
example E2.1: "raborated" should be "roborated".
- page 29, equation E2.26: replace
x
by |x| (two times). Also, the last words of this
problem should be "electric field of a dipole" not "electric field
of dipoles".
- page 32-33, between exercise E3X.3 and E3X.4: there is a
serious conceptual error here concerning the "infinite plate
approximation." The argument summarized in Figure E3.2 is wrong;
due to the fact that the amount of charge a given distance
r from the point increase as r^2, distant sections
of the plate cannot be ignored. If the plate's surface
charge is indeed uniform, then the perpendicular component
of the electric field at a point close to the plate is not much
affected by distant sections, but this is because these distant
sections create contributions to the electric field that are
almost completely parallel to the plate, not because they are
distant. The component of the field parallel to the plate
increases approximately linearly as one moves away from the
center, even very close to the plate. It is also worth noting that
if one places charge on an isolated conducting circular plate, the
equilibrium charge distribution is not even close to being
uniform, though the charge on two conducting circular plates
placed a small distance apart is pretty close to uniform,
because of the way the fields of the plates combine. I apologize
for this error (thanks to Stephen Baker of Rice University for
pointing it out). I am going to have to rewrite this section
fairly thoroughly for the third edition and modify Figure E3.2.
- page 33, sentence above equation E3.5:
change "If plug" to "If we plug".
- page 40, second paragraph, third line: time is 2.5 x 10^-14 s
not 5 x 10^-14 s.
- page 40, second paragraph, fifth line, after comma: should
read "an electron" not "a copper atom".
- page 41, summary, item IV.C.4: The
expression for the current I should not
contain <delta>t.
- page 41, summary, item V.A.2: units of current density should
be A/m^2, not A/m^3.
- page 55, last sentence in the paragraph
below E4.17: delete one of the repeated words "energy".
- page 56, last sentence in the last
paragraph before the exercise: "hydrogen ions" should be
"hydronium ions".
- page 90, equation E6.25: the final
quantity should be 0.5 V, not 0.5 A.
- page 95: content in the middle of the
page (as well as Figure E7.4) needs adjusting to be consistent
with the new content on pages 32 and 33. The basic issue here is
that at points near to two large plates (but far from the rims),
the components of the electric field vectors that are not
perpendicular to the plates essentially cancel. This makes the
field between and on either side of the plates essentially
perpendicular to the plates. (This also has the side effect of
redistributing the charge on the conducting plates so that the
charge density is essentially constant.)
- page 115, line above exercise E8X.8:
change "E8.5.4" to "E8X.8".
- page 162, problem E11A.1, first line after equation E11.26:
reference should be to equation E11.25, not E11.24. Also, change
"most mathematical" to "most general mathematical".
- page 185, equation E13.20: the
expression for the z-curl of the magnetic field should be:
- page 188: Problem E13S.1 should make it
clear that we are talking about concentric spherical shells
here.
- page 188, problem E13R.2, third line:
change "100 MN/C" to "10 MN/C".
- page 204, problem E14S.4, next-to-last
line: "curl(B)" should be "curl(B)_z".
- page 236, last line before equation
E17.20: change "units a of" to "units
of a".
- page 242, problem E17S.4, first line:
put a "~" or "very roughly" before "10^9 N/C".
- page 242, problem E17R.2, third line:
change "10 cm" to "20 cm".
- page 242, problem E17R.2, last line:
change "increased to 20 cm" to "decreased to 10 cm".
Go back to the
index
or go on to second-printing errors in unit
Q.