In a magneto-optic experiment, a liquid sample in a 10 -mL spherical vial is
placed in a highly uniform magnetic field, and a laser beam is directed
through the sample. Which of the following should be used to create the
uniform magnetic field required by the experiment?
a) a 5-cm-diameter flat coil consisting of one turn of 4-gauge wire
b) a 10 -cm-diameter, 20 turn, single layer, tightly wound coil made of 18
-gauge wire
c) a 2 -cm-diameter, 10 -cm long, tightly wound solenoid made of 18 -gauge
wire
d) a set of two coaxial 10 -cm-diameter coils at a distance of \(5
\mathrm{~cm}\) apart, each consisting of one turn of 4 -gauge wire