71.
(a) The impedance is
Z =
E
m
I
=
125 V
3.20 A
= 39.1 Ω .
(b) From V
R
= IR =
E
m
cos φ, we g et
R =
E
m
cos φ
I
=
(125 V) cos(0.982 rad)
3.20 A
= 21.7 Ω .
(c) Since X
L
−X
C
∝ sin φ = sin(−0.982 rad), we conclude that X
L
< X
C
. The circuit is predominantly
capacitive.