Question 1

The top diagram shows the velocity of a positively charged particle. The direction of the magnetic field due to the moving charge at r is best represented by

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) A) and E)
G) A) and D)

Question 2

Two very long, parallel conducting wires carry equal currents in opposite directions. The numbered diagrams show end views of the wires and the resultant force vectors due to current flow in each wire. Which diagram best represents the direction of the forces?

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) A) and E)
G) C) and E)

Question 3

When the positive current in a long wire is flowing in a direction from S to N, it creates a magnetic field below the wire that is directed

Accepted Answer

A)   from E to W.
B)   from N to S.
C)   from NE to SW.
D)   from S to N.
E)   from W to E.F) B) and E)
G) B) and D)

Question 4

Calculate the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I. (Note the loop and wire are not in electrical contact.)

Accepted Answer

A)   3.14
B)   1.00
C)   2.00
D)   0.318
E)   0.500F) A) and C)
G) B) and C)

Question 5

A long solenoid is wound around a silver core ( χ\chiχ m = -2.6 *10-5)  and carries a current. If the core is removed while the current is held constant, the magnetic field inside the solenoid

Accepted Answer

A)   remains constant.
B)   increases by approximately 0.003%.
C)   decreases by approximately 0.003%.
D)   increases by approximately 0.007%.
E)   decreases by approximately 0.006%. F) A) and C)
G) C) and D)

Question 6

Use the following to answer the next question: -5 T B)  8.5*10-6 T C)  3.3 *10-5 T D)  1.7* 10-5 T E)  none of the above" class="answers-bank-image d-inline" rel="preload" >
-Two long parallel wires are a distance d apart (d = 6 cm)  and carry equal and opposite currents of 5 A. Point P is distance d from each of the wires. Calculate the magnitude of the magnetic field strength at point P.

Accepted Answer

A)   2.9 * 10-5 T
B)   8.5*10-6 T
C)   3.3 *10-5 T
D)   1.7* 10-5 T
E)   none of the aboveF) A) and B)
G) All of the above

Question 7

A cylindrical bar magnet of radius 1.0 cm and length 10 cm has a magnetic dipole moment of magnitude m = 2.0 A · m2. What is the magnetic field just outside one end of the magnet?

Accepted Answer

A)   40 mT
B)   80 mT
C)   32 mT
D)   65 mT
E)   93 mTF) A) and B)
G) D) and E)

Question 8

Gauss's law for magnetism summarizes the fact(s)  that

Accepted Answer

A)   the magnetic flux through a closed surface is zero.
B)   the magnetic flux is given by SB dA. 
C)   the existence of magnetic monopoles has yet to be verified. 
D)   there is no point in space from which magnetic field lines diverge. 
E)   all of the above are true." class="answers-bank-image d-inline" rel="preload" > SB dA.
C)   the existence of magnetic monopoles has yet to be verified.
D)   there is no point in space from which magnetic field lines diverge.
E)   all of the above are true.F) C) and E)
G) A) and B)

Question 9

A 1000-turn solenoid is 50 cm long and has a radius of 2.0 cm. It carries a current of 8.0 A. What is the magnetic field inside the solenoid near its center?

Accepted Answer

A)   2.0 * 10-2 T
B)   3.2 * 10-3 T
C)   4.0 * 10-4 T
D)   1.0 T
E)   2.0 * 10-4 TF) B) and C)
G) A) and D)

Question 10

Two straight rods 60 cm long and 2.0 mm apart in a current balance carry currents of 18 A each in opposite directions. What mass must be placed on the upper rod to balance the magnetic force of repulsion?

Accepted Answer

A)   0.50 g
B)   0.99 g
C)   9.7 g
D)   4.3 g
E)   1.6 gF) D) and E)
G) None of the above

Question 11

An electron beam travels counterclockwise in a circle in the magnetic field produced by the Helmholtz coils, as shown. Assuming that Earth's field is downward, one can conclude that

Accepted Answer

A)   the Helmholtz field equals Earth's field.
B)   the current in the coils moves in the same direction as the electron beam.
C)   the current in the coils moves in the direction opposite to the electron beam.
D)   the Helmholtz field curves in the direction of the electron beam.
E)   the Helmholtz field curves in a direction opposite to the electron beam.F) B) and D)
G) C) and D)

Question 12

Diamagnetic materials

Accepted Answer

A)   have very small values of magnetic susceptibility  χ\chiχ m.
B)   have negative values of magnetic susceptibility  χ\chiχ m.
C)   produce very small induced magnetic moments.
D)   experience small repulsive forces when placed in external magnetic fields.
E)   are described by all of these. F) A) and B)
G) A) and C)

Question 13

A long solenoid with 15 turns per centimeter has a core of annealed iron. When the current is 1.00 A, the magnetic field inside the iron core is 2.46 T. The relative permeability Km is approximately

Accepted Answer

A)   1800
B)   1310
C)   7.64 * 10-4 
D)   5.56 * 10-4 
E)   1500F) C) and D)
G) B) and D)

Question 14

At a certain instant of time a particle with charge q = 25  μ\muμ C is located at x = 4.0 m, y = 2.0 m; its velocity at that time is v = -20 m/s  . If you are at the origin, what do you measure as the magnitude of the magnetic field due to this moving point charge?

Accepted Answer

A)   6.8 pT
B)   1.1 pT
C)   5.6 pT
D)   2.2 pT
E)   4.4 pT F) B) and C)
G) A) and B)

Question 15

A wire of radius 0.6 cm carries a current of 10 A that is uniformly distributed over its cross section. Calculate the magnetic field strength at r = 0.3 cm divided by that at r = 0.9 cm.

Accepted Answer

A)   1.0
B)   0.75
C)   0.50
D)   2.0
E)   3.0F) B) and C)
G) B) and D)

Exam 7: Sources of the Magnetic Field

Calculate the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I. (Note the loop and wire are not in electrical contact.)

Correct Answer
verified

Two straight rods 60 cm long and 2.0 mm apart in a current balance carry currents of 18 A each in opposite directions. What mass must be placed on the upper rod to balance the magnetic force of repulsion?

Correct Answer
verified

A 1000-turn solenoid is 50 cm long and has a radius of 2.0 cm. It carries a current of 8.0 A. What is the magnetic field inside the solenoid near its center?

Correct Answer
verified

A wire of radius 0.6 cm carries a current of 10 A that is uniformly distributed over its cross section. Calculate the magnetic field strength at r = 0.3 cm divided by that at r = 0.9 cm.

Correct Answer
verified

Two very long, parallel conducting wires carry equal currents in opposite directions. The numbered diagrams show end views of the wires and the resultant force vectors due to current flow in each wire. Which diagram best represents the direction of the forces?

Correct Answer
verified

Gauss's law for magnetism summarizes the fact(s) that

Correct Answer
verified

Diamagnetic materials

Correct Answer
verified

A cylindrical bar magnet of radius 1.0 cm and length 10 cm has a magnetic dipole moment of magnitude m = 2.0 A · m². What is the magnetic field just outside one end of the magnet?

Correct Answer
verified

An electron beam travels counterclockwise in a circle in the magnetic field produced by the Helmholtz coils, as shown. Assuming that Earth's field is downward, one can conclude that

Correct Answer
verified

A long solenoid with 15 turns per centimeter has a core of annealed iron. When the current is 1.00 A, the magnetic field inside the iron core is 2.46 T. The relative permeability K_m is approximately

Correct Answer
verified

Correct Answer
verified

The top diagram shows the velocity of a positively charged particle. The direction of the magnetic field due to the moving charge at r is best represented by

Correct Answer
verified

A long solenoid is wound around a silver core ( $\chi$ _m = -2.6 *10^-5) and carries a current. If the core is removed while the current is held constant, the magnetic field inside the solenoid

Correct Answer
verified

When the positive current in a long wire is flowing in a direction from S to N, it creates a magnetic field below the wire that is directed

Correct Answer
verified

Use the following to answer the next question: -Two long parallel wires are a distance d apart (d = 6 cm) and carry equal and opposite currents of 5 A. Point P is distance d from each of the wires. Calculate the magnitude of the magnetic field strength at point P.

Correct Answer
verified

Exam 7: Sources of the Magnetic Field

Calculate the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I. (Note the loop and wire are not in electrical contact.)

Correct AnswerverifiedShow Answer

Two straight rods 60 cm long and 2.0 mm apart in a current balance carry currents of 18 A each in opposite directions. What mass must be placed on the upper rod to balance the magnetic force of repulsion?

Correct AnswerverifiedShow Answer

A 1000-turn solenoid is 50 cm long and has a radius of 2.0 cm. It carries a current of 8.0 A. What is the magnetic field inside the solenoid near its center?

Correct AnswerverifiedShow Answer

A wire of radius 0.6 cm carries a current of 10 A that is uniformly distributed over its cross section. Calculate the magnetic field strength at r = 0.3 cm divided by that at r = 0.9 cm.

Correct AnswerverifiedShow Answer

Two very long, parallel conducting wires carry equal currents in opposite directions. The numbered diagrams show end views of the wires and the resultant force vectors due to current flow in each wire. Which diagram best represents the direction of the forces?

Correct AnswerverifiedShow Answer

Gauss's law for magnetism summarizes the fact(s) that

Correct AnswerverifiedShow Answer

Diamagnetic materials

Correct AnswerverifiedShow Answer

A cylindrical bar magnet of radius 1.0 cm and length 10 cm has a magnetic dipole moment of magnitude m = 2.0 A · m2. What is the magnetic field just outside one end of the magnet?

Correct AnswerverifiedShow Answer

An electron beam travels counterclockwise in a circle in the magnetic field produced by the Helmholtz coils, as shown. Assuming that Earth's field is downward, one can conclude that

Correct AnswerverifiedShow Answer

A long solenoid with 15 turns per centimeter has a core of annealed iron. When the current is 1.00 A, the magnetic field inside the iron core is 2.46 T. The relative permeability Km is approximately

Correct AnswerverifiedShow Answer

At a certain instant of time a particle with charge q = 25 μ\muμ C is located at x = 4.0 m, y = 2.0 m; its velocity at that time is v = -20 m/s . If you are at the origin, what do you measure as the magnitude of the magnetic field due to this moving point charge?

Correct AnswerverifiedShow Answer

The top diagram shows the velocity of a positively charged particle. The direction of the magnetic field due to the moving charge at r is best represented by

Correct AnswerverifiedShow Answer

A long solenoid is wound around a silver core ( χ\chiχ m = -2.6 *10-5) and carries a current. If the core is removed while the current is held constant, the magnetic field inside the solenoid

Correct AnswerverifiedShow Answer

When the positive current in a long wire is flowing in a direction from S to N, it creates a magnetic field below the wire that is directed

Correct AnswerverifiedShow Answer

Use the following to answer the next question: -Two long parallel wires are a distance d apart (d = 6 cm) and carry equal and opposite currents of 5 A. Point P is distance d from each of the wires. Calculate the magnitude of the magnetic field strength at point P.

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A cylindrical bar magnet of radius 1.0 cm and length 10 cm has a magnetic dipole moment of magnitude m = 2.0 A · m². What is the magnetic field just outside one end of the magnet?

Correct Answer
verified

Correct Answer
verified

A long solenoid with 15 turns per centimeter has a core of annealed iron. When the current is 1.00 A, the magnetic field inside the iron core is 2.46 T. The relative permeability K_m is approximately

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A long solenoid is wound around a silver core ( $\chi$ _m = -2.6 *10^-5) and carries a current. If the core is removed while the current is held constant, the magnetic field inside the solenoid

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified