Transcript Two long parallel wires 20 cm apart carry currents of 5A

Two long parallel wires 20 cm apart carry currents of 5A
and 8A in the same direction. Is there any point
between the two wires where the magnetic field is zero?
1. Yes, midway
between the wires.
2. Yes, 12 cm from
the 5A wire.
3. Yes, 7.7 cm from
the 5A wire.
4. No.
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A rectangular coil (0.20 m x 0.80 m) has 200 turns and is in a
uniform magnetic field of 0.30 T. If the orientation of the coil is
varied through all possible positions, the maximum torque on the
coil by magnetic forces is 0.080 N-m. What is the current in the
coil?
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5.0 mA
1.7 A
8.3 mA
1.0 A
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A circular coil (radius = 0.40 m) has 160 turns and is in a uniform
magnetic field. If the orientation of the coil is varied through all
possible positions, the maximum torque on the coil by magnetic
forces is 0.16 N-m when the current in the coil is 4.0 mA. What is
the magnitude of the magnetic field?
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0.37 T
1.6 T
0.50 T
1.2 T
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A high-voltage powerline 20 m above the ground carries
a current of 2000 A. What is the magnetic field due to
the current directly underneath the powerline? (µ 0 =
4∏ x 10-7 T-m/A)
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20.0 µ T
35.0 µ T
14.0 mT
0.3 T
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A superconducting solenoid is to be designed to
generate a magnetic field of 10 T. If the solenoid
winding has 2000 turns/meter, what is the required
current? (µ 0 = 4∏ x 10-7 A-m/T)
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1000 A
1990 A
3980 A
5000 A
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An incredible amount of electrical energy passes down the
funnel of a large tornado every second. Measurements taken in
Oklahoma at a distance of 9 km from a large tornado showed an
almost constant magnetic field of 1.5 x 10-8 T associated with
the tornado. What was the average current -going down the
funnel? (µ 0 = 4∏ x 10-7 A-m/T)
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150 A
250 A
350 A
500 A
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Superconductors are capable of carrying very large currents with
no resistance. If a superconducting wire is formed into a solenoid of
length 50 cm with 500 turns, what is the magnetic field inside the
solenoid when the current is 104 A? ( µ 0 = 4∏ x 10-7 A-m/T)
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1.25 T
2.50 T
6.28 T
12.6 T
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In a mass spectrometer, an ion will have a
smaller radius for its circular path if
1. its speed is greater
2. its mass is greater
3. its charge is
greater
4. the magnetic field
is weaker
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A current in a long, straight wire produces
a magnetic field, and these magnetic field
lines
1. go out from the wire to
infinity
2. come in from infinity
to the wire
3. form circles which
pass through the wire
4. form circles which go
around the circle
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Consider two long, straight parallel wires,
each carrying a current I. If the currents
are flowing in opposite directions
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2.
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the two wires will attract
each other
the two wires will repel
each other
the two wires will exert a
torque on each other
neither wire will exert a
force on the other
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When a magnetic field causes a charged particle to
move in a circular path, the only quantity listed below
which the magnetic force changes significantly as the
particle goes around in a circle is the particle's
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energy
momentum
radius for the circle
time to go around
the circle once
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A superconducting wire carries a current of 104
A. Find the magnetic field at a distance of 1.0 m
from the wire. ( µ 0 = 4∏ x 10-7 A-m/T)
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2.0 x 10-3 T
8.0 x 10-3 T
1.6 x 10-2 T
3.2 x 10-2 T
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There is a current I flowing in a clockwise direction in a square loop
of wire that is in the plane of the paper. If the magnetic field B is
toward the right, and if each side of the loop has length L, then the
net magnetic torque acting on the loop is
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2ILB
ILB
IBL2
zero
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A galvanometer can be used to make either an
ammeter or a voltmeter. Under which condition will the
deflection of the needle be greatest when a very small
current flows through the device?
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the current goes through the
original galvanometer.
the current goes through the
voltmeter.
the voltmeter and the original
galvanometer will give the
same deflection if the current is
the same.
the current goes through the
ammeter.
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There is a current I flowing in a clockwise direction in a square loop
of wire that is in the plane of the paper. If the magnetic field B is
toward the right, and if each side of the loop has length L, then the
net magnetic force acting on the loop is
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ILB
IBL2
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An electron which moves with a speed of 3 x 104 m/s
perpendicular to a uniform magnetic field of 0.40 T
experiences a force of what magnitude? (qe = 1.6 x
10-19 C)
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2.
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4.
4.8 x 10-14 N
19.2 x 10-16 N
2.2 x 10-24 N
zero
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A 2.0 m wire segment carrying a current of 0.60
A oriented parallel to a uniform magnetic field of
0.50 T experiences a force of what magnitude?
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4.
6.7 N
0.30 N
0.15 N
zero
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A proton moving with a speed of 3 x 105 m/s
perpendicular to a uniform magnetic field of 0.20 T will
follow which of the paths described below? (qe = 1.6 x
10-19 C and mp = 1.67 x 10-27 kg)
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2.
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a straight line path
a circular path of 1.5 cm
radius
a circular path of 3.0 cm
radius
a circular path of 0.75
cm radius
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If a deuteron, with the same charge but twice the mass of a proton,
were to move with a speed of 3 x 105 m/s perpendicular to a
uniform magnetic field of 0.20 T, it would follow which of the paths
described below? (qp = 1.6 x 10-19 C and md = 3.34 x 10-27 kg)
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2.
3.
4.
a straight line path
a circular path of 1.5 cm
radius
a circular path of 3.0 cm
radius
a circular path of 0.75
cm radius
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If a proton is released at the equator and falls toward
the Earth under the influence of gravity, the magnetic
force on the proton will be toward the
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north
south
east
west
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A stationary positive charge +Q, located in a magnetic
field B, which is directed toward the right as indicated.
The direction of the magnetic force on Q is
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toward the right
up
down
there is no magnetic
force
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A wire is lying horizontally in the north-south direction and the
horizontal magnetic field is toward the east. There are some
positive charges in the wire moving north and equal number of
negative charges moving south. The direction of the force on the
wire will be
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2.
3.
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east
down, into the page
up, out of the page
there is no magnetic
force
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There is a magnetic force on a particle. It
is possible that the particle is
1. uncharged
2. stationary
3. moving in the
direction of the
magnetic field
4. not part of a wire
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Electrical charges and magnetic poles
have many similarities. However, one
difference between the two is that
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opposite magnetic poles
repel
one magnetic pole cannot
create magnetic poles in
other materials
a magnetic pole cannot
be isolated
magnetic poles do not
produce magnetic fields
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Two singly ionized isotopes, X and Y, of the same element
move with the same speed perpendicular to a uniform
magnetic field. Isotope X follows a path of radius 3.35 cm
while isotope Y moves along a 3.43 cm radius path. What is
the ratio of the two isotope masses, mX /mY ?
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2.
3.
4.
0.977
1.023
1.048
0.954
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A 10 ohm, 25 mA galvanometer is to be converted into
an ammeter which reads 5 A at a full scale deflection.
What resistance should be placed in parallel with the
galvanometer coil?
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4.
2.5 ohms
0.5 ohms
0.25 ohms
0.05 ohms
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A proton which moves perpendicular to a magnetic field
of 1.2 T in a circular path of 0.08 m radius, has what
speed? (qp = 1.6 x 10-19 C and mp = 1.67 x 10 -27 kg)
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2.
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3.4 x 106 m/s
4.6 x 106 m/s
9.6 x 106 m/s
9.2 x 106 m/s
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A 10 ohm, 25 mA galvanometer is to be converted into a
voltmeter which reads 20 V at full scale deflection. What
resistance should be placed in series with the
galvanometer coil?
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2.
3.
4.
810 ohms
790 ohms
500 ohms
450 ohms
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A 10 ohm, 15 mA galvanometer is converted into an
ammeter by placing a 1.5 x 10-2 ohm shunt in parallel
with the galvanometer coil. What is the maximum scale
reading on the galvanometer?
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4.
25.0 A
15.0 A
10.0 A
5.0 A
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A circular loop carrying a current of 2.0 A is oriented in a magnetic
field of 3.5 T. The loop has an area of 0.12 m2 and is mounted on
an axis, perpendicular to the magnetic field, which allows the loop
to rotate. If the plane of the loop is oriented parallel to the field,
what torque is created by the interaction of the loop current and the
field?
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58 N-m
6.8 N-m
0.84 N-m
0.17 N-m
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A circular loop carrying a current of 2.0 A is oriented in a
magnetic field of 3.5 T. The loop has an area of 0.12 m2 and is
mounted on an axis, perpendicular to the magnetic field, which
allows the loop to rotate. What is the torque on the loop when its
plane is oriented at a 37° angle to the field?
25% 25% 25% 25%
1.
2.
3.
4.
46.0 N-m
0.67 N-m
0.51 N-m
0.10 N-m
1
2
3
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5
6
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31
32
33
41
42
43
44
45
46
47
48
49
50
1
14
15
34
35
2
16
17
36
37
3
18
19
38
39
4
20
40
A horizontal wire of length 3.0 m carries a current of 6.0 A and is
oriented so that the current direction is 50° S of W. The horizontal
component of the earth's magnetic field is due north at this point
and has a strength of 0.14 x 10-4 T. What is the direction of the
force on the wire?
1.
2.
3.
4.
out of the earth's surface
toward the earth's surface
due east
40° S of E
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
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31
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33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A current carrying wire of length 50 cm is positioned perpendicular
to a uniform magnetic field. If the current is 10.0 A and it is
determined that there is a resultant force of 3.0 N on the wire due
to the interaction of the current and field, what is the magnetic field
strength?
1.
2.
3.
4.
0.6 T
1.50 T
1.85 x 103 T
6.7 x 103 T
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
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33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A horizontal wire of length 3.0 m carries a current of 6.0 A and is
oriented so that the current direction is 50° S of W. The horizontal
component of the earth's magnetic field is due north at this point
and has a strength of 0.14 x 10-4 T. What is the size of the force on
the wire?
1.
2.
3.
4.
0.28 x 10-4 N
2.5 x 10-4 N
1.9 x 10-4 N
1.6 x 10-4 N
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
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30
31
32
33
34
35
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37
38
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40
41
42
43
44
45
46
47
48
49
50
An electron moves across the earth's equator at a speed of
2.5 x 106 m/s and in a direction 35° N of E. At this point the
earth's magnetic field has a direction due north, is parallel to
the surface, and has a value of 0.10 x 10-4 T. What is the
direction of the force acting on the electron at this instant?
1. due west
2. into the earth's
surface
3. out of the earth's
surface
4. due south
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A proton is released such that it has an initial speed of 4 x
105 m/s from left to right across the page. A magnetic field of
1.2 T is present at an angle of 30° to the horizontal direction
(or positive x-axis). What is the magnitude of the force
experienced by the proton? (qp = 1.6 x 10-19 C)
25% 25% 25% 25%
1.
2.
3.
4.
4.8 x 10-25 N
1.3 x 10-19 N
3.8 x 10-14 N
7.5 x 103 N
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
An electron moves across the earth's equator at a speed of 2.5 x 106 m/s
and in a direction 35° N of E. At this point the earth's magnetic field has a
direction due north, is parallel to the surface, and has a value of 0.10 x
10-4 T. What is the magnitude of the force acting on the electron due to its
interaction with the earth's magnetic field? (qe = -1.6 x 10-19 C)
25% 25% 25% 25%
10-18
1.
2.
3.
4.
5.1 x
N
4.0 x 10-18 N
3.3 x 10-18 N
2.3 x 10-18 N
1
2
3
4
5
6
7
8
9
10
11
12
13 1 14
15
21
22
23
24
25
26
27
28
29
30
31
32
33
35
41
42
43
44
45
46
47
48
49
50
34
2
16
17
36
37
3
18
19
4 20
38
39
40
A proton is released such that its initial velocity is from right to left
across this page. The proton's path, however, is deflected in a
direction toward the bottom edge of the page due to the presence
of a uniform magnetic field. What is the direction of this field?
1.
2.
3.
4.
out of the page
into the page
from bottom edge to top
edge of the page
from right to left across
the page
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Geo-physicists today generally attribute
the existence of the earth's magnetic field
to which of the following?
1. convection currents
within the liquid
interior
2. iron ore deposits in
the crust
3. nickel-iron deposits in
the crust
4. solar flares
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The term magnetic declination refers to
which of the following?
1.
2.
3.
4.
angle between earth's
magnetic field and earth's
surface
earth's magnetic field strength
at the equator
tendency for earth's field to
reverse itself
angle between directions to
true north and magnetic north
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The magnetic field of the earth is believed
responsible for which of the following?
1.
2.
3.
4.
deflection of both charged
and uncharged cosmic
rays
deflection of charged
cosmic rays
ozone in the upper
atmosphere
solar flares
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Assume that a uniform magnetic field is directed into this page. If
an electron is released with an initial velocity directed from the
bottom edge to the top edge of the page, which of the following
describes the direction of the resultant force acting on the electron?
1.
2.
3.
4.
out of the page
to the right
to the left
into the page
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A current in a solenoid with N turns creates a magnetic
field at the center of that loop. The field strength is
directly proportional to which of the following?
1. number turns in
loop
2. current strength
3. both of the choices
are valid
4. none of the choices
are valid
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A circular current loop is placed in an
external magnetic field. How is the torque
related to the radius of the loop?
1. directly proportional to
radius
2. inversely proportional
to radius
3. directly proportional to
radius squared
4. inversely proportional
to radius squared
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The path of a charge particle moving
parallel to a uniform magnetic field will be
which of the following?
1.
2.
3.
4.
straight line
circle
ellipse
parabola
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The current in a long wire creates a magnetic field in the
region around the wire. How is the strength of that field
at a given distance, r, from the wire center related to the
magnitude of the field?
25% 25% 25% 25%
1.
2.
field directly proportional to r
field inversely proportional
to r
field directly proportional to
r2
field inversely proportional
to r2
3.
4.
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The direction of the force on a current
carrying wire located in an external
magnetic field is which of the following?
1. perpendicular to the
current
2. perpendicular to the
field
3. both of the choices
are valid
4. none of the choices
are valid
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A current in a solenoid coil creates a magnetic
field inside that coil. The field strength is directly
proportional to which of the following?
1. coil area
2. current
3. both current and
coil area
4. none of these
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Which of the following devices makes use of
an electromagnet?
1.
2.
3.
4.
loudspeaker
galvanometer
both of the choices
none of the choices
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The magnetic domains in a nonmagnetized piece of iron are
characterized by which orientation?
1.
2.
3.
4.
parallel to the magnetic
axis
anti-parallel to the
magnetic axis
random
perpendicular to the
magnetic axis
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The force on a charged particle created by its
motion in a magnetic field is maximum at what
angle between the particle velocity and field?
1.
2.
3.
4.
zero
180°
90°
45°
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A solenoid with 500 turns, 0.10 m long, carrying a
current of 4.0 A and with a radius of 10-2 m will have
what strength magnetic field at its center? (magnetic
permeability in empty space µ 0 = 4∏ x 10 -7 T-m/A)
1.
2.
3.
4.
31 x 10-4 T
62 x 10-4 T
125 x 10-4 T
250 x 10-4 T
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
The force exerted on a current carrying wire
located in an external magnetic field is directly
proportional to which of the following?
1.
2.
3.
4.
current strength
field strength
both of the choices
none of the choices
are valid
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A thin copper rod 1.0 m long has a mass of 50 grams.
What is the minimum current in the rod that would allow
it to "float" in a magnetic field of 0.1T?
1.
2.
3.
4.
1.23 A
2.45 A
4.9 A
9.8 A
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A 100 m long wire carrying a current of 4.0 A will be
accompanied by a magnetic field of what strength at a
distance of 0.05 m from the wire? (magnetic
permeability in empty space µ 0 = 4∏ x 10-7 T-m/A)
1.
2.
3.
4.
4.0 x 10-5 T
2.0 x 10-5 T
1.6 x 10-5 T
zero
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Two parallel conductors each of 0.5 m length, separated by 5 x
10-3 m and carrying 3.0 A in opposite directions, will experience
what type and magnitude of mutual force? (magnetic
permeability in empty space µ 0 = 4∏ x 10-7 T-m/A)
25% 25% 25% 25%
attractive, 0.06 x 10-4 N
repulsive, 0.60 x 10-4 N
attractive, 1.8 x 10-4 N
repulsive, 1.8 x 10-4 N
1.
2.
3.
4.
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
At the Fermilab accelerator in Weston, Illinois, protons with
momentum 4.8 x 10-16 kg-m/s are held in a circular orbit of
radius 1 km by an upward magnetic field. What upward Bfield must be used to maintain the protons in this orbit? (qp
= 1.6 x 10-19 C)
25% 25% 25% 25%
1.
2.
3.
4.
1T
2T
3T
4T
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
An electron moves through a region of crossed electric and
magnetic fields. The electric field E = 1000 V/m and is directed
straight down. The magnetic field B = 0.4 T and is directed to the
left. For what velocity v of the electron into the paper will the
electric force exactly cancel the magnetic force?
1.
2.
3.
4.
25% 25% 25% 25%
2500 m/s
4000 m/s
5000 m/s
8000 m/s
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Niobium metal becomes a superconductor (with electrical
resistance equal to zero) when cooled below 9 K. If
superconductivity is destroyed when the surface magnetic field
exceeds 0.1 T, determine the maximum current a 4-mm diameter
niobium wire can carry and remain superconducting. ( µ 0 = 4∏
x 10-7 A-m/T)
25% 25% 25% 25%
1.
2.
3.
4.
125 A
250 A
500 A
1000 A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
1
33
34
2
35
36
3
37
38
394
40
41
42
43
44
45
46
47
48
49
50
A proton, mass 1.67 x 10-27 kg and charge +1.6 x 10-19
C, moves in a circular orbit perpendicular to a uniform
magnetic field of 0.75 T. Find the time for the proton to
make one complete circular orbit.
1.
2.
3.
4.
4.3 x 10-8 s
8.7 x 10-8 s
4.9 x 10-7 s
9.8 x 10-7 s
25% 25% 25% 25%
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50