11. A circular wire loop of radius R = 10 cm carries a current of 2.5 A. The magnetic field in the center of the loop is:
a) 1.05x10^-5 T
b) 7.85x10^-6 T
c) 6.28x10^-6 T
d) 3.48x10^-5 T
e) 1.57x10^-5 T
12. A current I = 1.5 A is carried by a long wire in the plane of the page, as shown. A loop of width a = 10 cm and height b = 15 cm lies in the plane of the page next to the wire. The right edge of the loop is at a distance s = 5 cm from the wire. The total magnetic flux passing through the loop is:
a) 3.79x10^-8 T·m^2
b) 8.24x10^-8 T·m^2
c) 1.15x10^-7 T·m^2
d) 1.48x10^-7 T·m^2
e) 4.94x10^-8 T·m^2
13. A conducting ring is moving down through a region of uniform magnetic field with the field pointing out of the page, as shown. The current induced in the ring in the (top, middle, bottom) position is:
a) (clockwise, zero, counterclockwise)
b) (counterclockwise, zero, clockwise)
c) (zero, clockwise, zero)
d) (zero, counterclockwise, zero)
e) (zero, zero, zero)