True-false questions are worth 2 points each, three-choice multiple
choice questions are worth 3 points each, five-choice multiple choice
questions are worth 6 points each. The maximum possible score is 117.
The exam period was 90 minutes; the mean was 94.1; the median was 98.
Click here to see page1
page2 of the formula sheet that came
with the exam.
The figure depicts a square wire coil with 4 loops. The length of
each side of the square is L. The coil is situated in a region of
constant magnetic field B = 0.2 T pointing in the
+y direction. A current I = 20 amps flows in the coil in
the direction shown (the black arrowhead indicates the current direction
on the side of the square nearest you.) The square coil makes an angle
of α with the xz-plane and the coil has a magnetic dipole
moment with magnitude 25 A m2.
What is the length of a side of the square loop?
(a) L = 0.44 m
(b) L = 0.56 m
(c) L = 0.62 m
(a) 2.5 N m
(b) 3.3 N m
(c) 4.1 N m
(d) 4.6 N m
(e) 5.0 N m
(a) clockwise (decreasing α)
(b) counterclockwise (increasing α)
(a) α = 0°
(b) α = 45°
(c) α = 90°
(a) | ΔU | = 0.67 J
(b) | ΔU | = 1.00 J
(c) | ΔU | = 1.25 J
(d) | ΔU | = 2.00 J
(e) | ΔU | = 2.50 J
Two fixed conductors are connected by a resistor R = 20
Ω. The two fixed conductors are separated by L = 2.5 m and
lie horizontally. A moving conductor of mass m slides on them at a
constant speed v, producing a current of 3.75 amps. A
magnetic field (shown by the black dots in the figure) with magnitude 5
T points out of the page.
In which direction does the current flow through the moving conductor
when the bar is sliding in the direction shown?
(a) to the right
(b) to the left
(a) v = 1 m/s
(b) v = 3 m/s
(c) v = 5 m/s
(d) v = 6 m/s
(e) v = 9 m/s
(a) F = 28 N
(b) F = 37 N
(c) F = 47 N
The values of all circuit elements are given in the figure. The
capacitor is initially uncharged. Then, at time t = 0, the
switch is closed.
What is the current through the battery immediately after the
switch is closed?
(a) I = 0.6 A
(b) I = 0.9 A
(c) I = 1.2 A
(a) increases with time.
(b) decreases with time.
(c) remains constant with time.
(a) Q = 2.0 μC
(b) Q = 3.0 μC
(c) Q = 4.0 μC
(d) Q = 5.0 μC
(e) Q = 6.0 μC
(a) 2.4 μs
(b) 3.3 μs
(c) 6.7 μs
(d) 10.0 μs
(e) 30.0 μs
With the switch open, what is the current I1?
(A positive sign means that current flows in the direction of the
(a) -0.20 A
(b) -0.05 A
(c) +0.05 A
(d) +0.20 A
(e) +0.35 A
(a) 0.13 W
(b) 1.39 W
(c) 2.47 W
(a) 0.05 A
(b) 0.09 A
(c) 0.12 A
(d) 0.33 A
(e) 0.47 A
(a) VA - VB = 10 - 10 I1 - 5 I2
(b) VA - VB = 10 + 10 I1 + 5 I2
(c) VA - VB = -6 + 50 I1 + 15 I2
(d) VA - VB = 6 + 50 I1 - 15 I2
(e) VA - VB = 6 - 50 I1 + 15 I2
Which one of the plots at right best represents the induced current in the
loop (Iloop) as a function of its position as it
travels from the left through these three regions. Note: A
positive Iloop means that current flows
Consider the two cases shown below. In each case a conductor carries
the same total current I = 2 amps into the page, and in each case
the current is uniformly distributed over the cross-section of the
In Case 1 the conductor is a cylindrical shell of outer radius
R0 = 10 cm and inner radius R1 = 7.5
cm. In Case 2 the conductor is a solid cylinder having the same outer
radius R0 = 10 cm.
Compare B1(a), the magnitude of the magnetic
field at point a (r = 5 cm) in Case 1, to
B2(a), the magnitude of the magnetic field at
point a (r = 5 cm) in Case 2.
(a) B1(a) < B2(a)
(b) B1(a) = B2(a)
(c) B1(a) > B2(a)
(a) -2.67 × 10-6 T
(b) -1.33 × 10-6 T
(c) 0 T
(d) 1.33 × 10-6 T
(e) 2.67 × 10-6 T
Which one of the statements at right best describes the integral of
B.dL along just the left most segment of the path
(i.e. b → c)?
An infinite solid cylindrical conductor of radius a = 3 cm
centered on the z-axis carries a current I1 = 1
A. The current is uniformly distributed over its cross section and is
directed out of the page (positive z-direction). A coaxial
infinite, thin cylindrical conducting shell of radius b = 8 cm
carries a current I2 = 4 A, into the page
What is the magnitude of the B field inside the inner cylinder
at a radius of 2.0 cm from the central axis?
(b) 1.79 × 10-6 T
(c) 2.77 × 10-6 T
(d) 3.58 × 10-6 T
(e) 4.44 × 10-6 T
(a) The diamagnetic material is repelled by the magnet.
(b) The diamagnetic material is not attracted or repelled by the magnet.
(c) The diamagnetic material is attracted to the magnet.
(a) The paramagnetic material is repelled by the magnet.
(b) The paramagnetic material is not attracted or repelled by the magnet.
(c) The paramagnetic material is attracted to the magnet.
A negatively charged particle (q < 0) enters a
region with uniform magnetic field B =
Boz. (The region with the field is shaded.) The
particle has initial velocity v = voy
along the y axis as shown at right.
The particle bends around in a semicircle and exits the field
region a distance L from the origin. Does it exit at x =
-L or at x = +L ?
(a) x = +L
(b) x = -L
(a) 2 vo / |q| Bo L
(b) Bo L / 2 |q| vo
(c) |q| L / Bo vo
(d) |q| Bo L / 2 vo
(e) |q| Bo / 2 L vo
(a) each wire experiences an attractive force, directed
towards the other wire.
(b) each wire experiences no net force.
(c) each wire experiences a repulsive force, directed away
from the other wire.