36.
(a) We use C = ε
0
A/d to solve for d:
d =
ε
0
A
C
=
8.85
× 10
−12 C
2
N
·m
2
(0.35 m
2
)
50
× 10
−12
F
= 6.2
× 10
−2
m .
(b) We use C
∝ κ. The new capacitance is C
= C(κ/κ
air
) = (50 pf)(5.6/1.0) = 280 pF.
36.
(a) We use C = ε
0
A/d to solve for d:
d =
ε
0
A
C
=
8.85
× 10
−12 C
2
N
·m
2
(0.35 m
2
)
50
× 10
−12
F
= 6.2
× 10
−2
m .
(b) We use C
∝ κ. The new capacitance is C
= C(κ/κ
air
) = (50 pf)(5.6/1.0) = 280 pF.