Transcript One long wire carries a current of 14 A along the entire
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Each of two long straight parallel wires separated by a distance of 16 cm carries a current of 17 A in the same direction. What is the magnitude of the resulting magnetic field at a point that is 12 cm from each wire?
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1. 4.0 A 2. 3.0 A 3. 0.7 A 4. 7.0 A 5. 8.0 A
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Each of two parallel wires separated by 8.5 mm carries a 20-A current. These two currents are oppositely directed. Determine the magnitude of the magnetic field at a point that is 5.0 mm from each of the wires.
1. 1.4 mT 2. 1.7 mT 3. 1.5 mT 4. 1.9 mT 5. 2.2 mT
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Two long parallel wires separated by 4.2 mm each carry a current of 40 A. These two currents are oppositely directed. What is the magnitude of the magnetic field at a point that is between the two wires and 2.5 mm from one of the two wires?
1. 7.9 mT 2. 8.1 mT 3. 7.4 mT 4. 8.9 mT 5. 9.1 mT
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Two long parallel wires separated by 4.3 mm each carry a current of 28 A. These two currents are in the same direction. What is the magnitude of the magnetic field at a point that is between the two wires and 1.1 mm from one of the two wires?
1. 3.3 mT 2. 3.8 mT 3. 3.9 mT 4. 4.3 mT 5. 1.5 mT
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1. 1.8 A 2. 1.5 A 3. 1.4 A 4. 2.3 A 5. 2.7 A
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A segment of wire of total length 2.4 m is formed into a circular loop having 4.0 turns. If the wire carries a 1.8-A current, determine the magnitude of the magnetic field at the center of the loop.
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0.39 mT 0.44 mT 0.49 mT 0.50 mT 0.54 mT
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1. 0.44 A 2. 0.22 A 3. 0.49 A 4. 44 mA 5. 22 mA
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1. 2 mN 2. 2.2 mN 3. 2.3 mN 4. 1.5 mN 5. 2.7 mN
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A long straight wire (diameter = 2.5 mm) carries a current of 30 A. What is the magnitude of the magnetic field 2.0 mm from the axis of the wire?
1. 3.0 mT 2. 3.5 mT 3. 2.4 mT 4. 2.0 mT 5. 4.1 mT
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22 mN 24 mN 25 mN 27 mN 16 mN
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1. 67 mN 2. 59 mN 3. 75 mN 4. 55 mN 5. 87 mN
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A hollow cylindrical conductor (inner radius = 1.0 mm, outer radius = 3.0 mm) carries a current of 90.0 A parallel to its axis. This current is uniformly distributed over a cross section of the conductor. Determine the magnitude of the magnetic field at a point that is 1.9 mm from the axis of the conductor.
1. 3.1 mT 2. 3.4 mT 3. 2.6 mT 4. 4.2 mT 5. 16 mT
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A long straight wire (diameter = 2.4 mm) carries a current of 27 A. What is the magnitude of the magnetic field 0.70 mm from the axis of the wire?
1. 2.6 mT 2. 2.4 mT 3. 30 mT 4. 0.18 mT 5. 0.17 mT
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A long hollow cylindrical conductor (inner radius = 2.0 mm, outer radius = 3.5 mm) carries a current of 20 A distributed uniformly across its cross section. A long wire which is coaxial with the cylinder carries an equal current in the opposite direction. What is the magnitude of the magnetic field 3.1 mm from the axis?
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1. 0.41 mT 2. 0.35 mT 3. 0.31 mT 4. 0.29 mT 5. 0.13 mT
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A long, straight wire (radius = 2.2 mm) carries a current of 3.9 A distributed uniformly over a cross section perpendicular to the axis of the wire. What is the magnitude of the magnetic field at a distance of 1.3 mm from the axis of the wire?
1. 0.21 mT 2. 0.18 mT 3. 0.24 mT 4. 0.26 mT 5. 0.15 mT
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A long solenoid (diameter = 5.1 cm) is wound with 910 turns per meter of thin wire through which a current of 280 mA is maintained. A wire carrying 15 A is inserted along the axis of the solenoid. What is the magnitude of the magnetic field at a point 2.1 cm from the axis?
1. 0.35 mT 2. 0.40 mT 3. 0.28 mT 4. 0.48 mT 5. 0.16 mT
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A long solenoid (1,200 turns/m) carries a current of 30 mA and has an inside radius of 1.9 cm. A long wire which is parallel to and 3.5 cm from the axis of the solenoid carries a current of 6.7 A. What is the magnitude of the magnetic field at a point on the axis of the solenoid?
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A long solenoid (1,400 turns/m) carries a current of 16 mA and has an inside diameter of 3.3 cm. A long wire carries a current of 2.2 A along the axis of the solenoid. What is the magnitude of the magnetic field at a point that is inside the solenoid and 1.2 cm from the wire?
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Which diagram correctly shows the magnetic field lines created by a circular current loop through which current flows in the direction shown?
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When the number of turns in a solenoid and its length are both doubled, what is the ratio of the magnitude of the new magnetic field inside to the magnitude of the original magnetic field inside?
1. 1 2. 2 3. 0.5
4. 0.25
5. 4
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The reason the south pole of a bar magnet free to rotate points south is because _____ .
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the south geographic pole of the earth is the earth's magnetic north pole the north geographic pole of the earth is the earth's magnetic north pole there is a net accumulation of negative magnetic charge at the earth's south geographic pole there is a net accumulation of positive magnetic charge at the earth's north geographic pole the south geographic pole of the earth is the earth's magnetic south pole
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At a point in space where the magnetic field is measured, the magnetic field produced by a current element _____ .
points in a direction that is perpendicular to the current element and perpendicular to the radial direction points radially in the direction from the point in space towards the current element points in a direction parallel to the current element points in a direction parallel to but opposite in direction to the current element points radially away in the direction from the current element to the point in space
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A toroid is made of 2,400 turns of wire of radius 2.10 cm formed into a donut shape of inner radius 10.1 cm and outer radius 14.3 cm. When a 36.0-A current is present in the toroid, the magnetic field at a distance of 10.5 cm from the center of the toroid is _____ .
1. 0.165 T 2. 0.160 T 3. 0.145 T 4. 0.143 T 5. 0.207 T
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A 0.60-m long solenoid consists of 1,000 turns of copper wire wound with a 4.4 cm radius. When the current in the solenoid is 17 A, what is the magnetic field at a point 1.0 cm from the central axis of the solenoid?
1. 36 mT 2. 33 mT 3. 23 mT 4. 0.36 mT 5. 0.33 mT
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A loose spiral spring is hung from the ceiling, and a large current is sent through it. The coils move _____.
1. closer together 2. farther apart 3. they do not move at all
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conduction current but no displacement current displacement current but no conduction current both conduction and displacement current no current of any type
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