3. We use Φ =
E
·
A, where
A = Aˆj = (1.40 m)
2
ˆj.
(a) Φ = (6.00 N/C)ˆi
· (1.40 m)
2
ˆj = 0.
(b) Φ = (
−2.00 N/C)ˆj· (1.40 m)
2
ˆj =
−3.92 N·m
2
/C.
(c) Φ = [(
−3.00 N/C)ˆi+ (4.00 N/C)ˆk] · (1.40 m)
2
ˆj = 0.
(d) The total flux of a uniform field through a closed surface is always zero.