2
.
Caution:
See the
sketch to confirm the location of the point A.
ˆ
i
−
ˆ
j
√
B
A
. Eval-
uate the loop integral along the rectangular
loop
CDEFC ,
where
EF
=
a
and
FC
=
b .
What is the magnitude of this loop integral?
Explanation:
Consider that the current sheet consists of
By symmetry, the direction of
vector
B
due to
an infinite current sheet is therefore along
positive
y
direction (ˆ
) in the part of space
where
x <
0.
007(part2of3)10.0points
Ampere’s Law states that
contintegraldisplay
vector
B
·
dvectors
=
µ
0
I
Denote the magnetic field at A by
B
A
. Eval-
uate the loop integral along the rectangular
loop
CDEFC ,
where
EF
=
a
and
FC
=
b .
What is the magnitude of this loop integral?
10.

an infinite number of current wires connected
in parallel.
We can easily determine the di-
rection of
vector
B
for one wire with right-hand rule.
Then the direction of
vector
B
for two wires set to-
gether in parallel can be found (as illustrated
below) by the superposition principle.
Consider the path
CDEFC
.