1 / 88

Chapter 27: Sources of the Magnetic Field

Chapter 27: Sources of the Magnetic Field . Section 27-1: The Magnetic Field of Moving Point Charges.

neveah
Download Presentation

Chapter 27: Sources of the Magnetic Field

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 27: Sources of the Magnetic Field Section 27-1: The Magnetic Field of Moving Point Charges

  2. A point charge is moving with constant speed 2 ×107 m/s along the x axis. It creates a magnetic field as it travels through a region where there is no external magnetic field. At t = 0, the charge is at x = 0 m and the magnitude of the magnetic field at x = 4 m is B0. The magnitude of the magnetic field at x = 4m when t = 0.1 s is • B0/2 • B0 • B0/4 • 2B0 • 4B0

  3. A point charge is moving with constant speed 2 ×107 m/s along the x axis. It creates a magnetic field as it travels through a region where there is no external magnetic field. At t = 0, the charge is at x = 0 m and the magnitude of the magnetic field at x = 4 m is B0. The magnitude of the magnetic field at x = 4m when t = 0.1 s is • B0/2 • B0 • B0/4 • 2B0 • 4B0

  4. The top diagram shows the velocity of a positively charged particle. Which arrow best represents the direction of the magnetic field due to the moving charge at r ?

  5. The top diagram shows the velocity of a positively charged particle. Which arrow best represents the direction of the magnetic field due to the moving charge at r ?

  6. The magnitude of the magnetic field due to the presence of a charged body • varies directly with the speed of the body. • varies directly with the charge carried by the body. • varies inversely with the square of the distance between the charged body and the field point. • depends on the magnetic properties of the space between the charged body and the field point. • is described by all of these.

  7. The magnitude of the magnetic field due to the presence of a charged body • varies directly with the speed of the body. • varies directly with the charge carried by the body. • varies inversely with the square of the distance between the charged body and the field point. • depends on the magnetic properties of the space between the charged body and the field point. • is described by all of these.

  8. A positively charged body is moving in the negative z direction as shown. What is the direction of the magnetic field due to the motion of this charged body at point P?

  9. A positively charged body is moving in the negative z direction as shown. What is the direction of the magnetic field due to the motion of this charged body at point P?

  10. A positively charged body is moving in the positive x direction as shown. The direction of the magnetic field at the origin due to the motion of this charged body is • 1 • 2 • 3 • 4 • None of these is correct, as this charged body does not create a magnetic field along the axis of its motion.

  11. A positively charged body is moving in the positive x direction as shown. The direction of the magnetic field at the origin due to the motion of this charged body is • 1 • 2 • 3 • 4 • None of these is correct, as this charged body does not create a magnetic field along the axis of its motion.

  12. At the instant the positively charged body is at the origin, the magnetic field at point P due to the motion of this charged body is in the negative x direction. The charged body must be moving • in the negative z direction. • in the positive y direction. • in the positive x direction. • in the negative y direction. • in the positive z direction.

  13. At the instant the positively charged body is at the origin, the magnetic field at point P due to the motion of this charged body is in the negative x direction. The charged body must be moving • in the negative z direction. • in the positive y direction. • in the positive x direction. • in the negative y direction. • in the positive z direction.

  14. At the instant the negatively charged body is at the origin, the magnetic field at point P due to its motion is in the negative x direction. The charged body must be moving • in the negative z direction. • in the positive y direction. • in the positive x direction. • in the negative y direction. • in the positive z direction.

  15. At the instant the negatively charged body is at the origin, the magnetic field at point P due to its motion is in the negative x direction. The charged body must be moving • in the negative z direction. • in the positive y direction. • in the positive x direction. • in the negative y direction. • in the positive z direction.

  16. Two positively charged bodies are moving in opposite directions on parallel paths that lie in the xz plane. Their speeds are equal and their trajectories are equidistant from the x axis. The magnetic field at the origin, due to the motion of these charged bodies will be • in the +x direction. • in the +y direction. • in the−y direction. • in the +z direction. • zero.

  17. Two positively charged bodies are moving in opposite directions on parallel paths that lie in the xz plane. Their speeds are equal and their trajectories are equidistant from the x axis. The magnetic field at the origin, due to the motion of these charged bodies will be • in the +x direction. • in the +y direction. • in the−y direction. • in the +z direction. • zero.

  18. Chapter 27: Sources of the Magnetic Field Section 27-2: The Magnetic Field of Currents: The Biot-Savart Law

  19. Two wires lying in the plane of this page carry equal currents in opposite directions, as shown. At a point midway between the wires, the magnetic field is • zero. • into the page. • out of the page. • toward the top or bottom of the page. • toward one of the two wires.

  20. Two wires lying in the plane of this page carry equal currents in opposite directions, as shown. At a point midway between the wires, the magnetic field is • zero. • into the page. • out of the page. • toward the top or bottom of the page. • toward one of the two wires.

  21. What is the direction of the magnetic field around a wire carrying a current perpendicularly into this page? • The field is parallel to and in the same direction as the current flow. • It is parallel to but directed opposite to the current flow. • It is counterclockwise around the wire in the plane of the page. • It is clockwise around the wire in the plane of the page. • None of these is correct.

  22. What is the direction of the magnetic field around a wire carrying a current perpendicularly into this page? • The field is parallel to and in the same direction as the current flow. • It is parallel to but directed opposite to the current flow. • It is counterclockwise around the wire in the plane of the page. • It is clockwise around the wire in the plane of the page. • None of these is correct.

  23. A wire carries an electric current straight upward. What is the direction of the magnetic field due to the current north of the wire? • north • east • west • south • upward

  24. A wire carries an electric current straight upward. What is the direction of the magnetic field due to the current north of the wire? • north • east • west • south • upward

  25. The Biot–Savart law is similar to Coulomb's law in that both • are inverse square laws. • include the permeability of free space. • deal with excess charges. • are not electrical in nature. • are described by all of these.

  26. The Biot–Savart law is similar to Coulomb's law in that both • are inverse square laws. • include the permeability of free space. • deal with excess charges. • are not electrical in nature. • are described by all of these.

  27. Two current-carrying wires are perpendicular to each other. The current in one flows vertically upward and the current in the other flows horizontally toward the east. The horizontal wire is 1 m south of the vertical wire. What is the direction of the net magnetic force on the horizontal wire? • north • east • west • south • There is no net magnetic force on the horizontal wire.

  28. Two current-carrying wires are perpendicular to each other. The current in one flows vertically upward and the current in the other flows horizontally toward the east. The horizontal wire is 1 m south of the vertical wire. What is the direction of the net magnetic force on the horizontal wire? • north • east • west • south • There is no net magnetic force on the horizontal wire.

  29. Each of the figures shown is the source of a magnetic field. In which figure does the magnetic dipole vector point in the direction of the negative x axis? (Note: in C and D the arrows show the direction of the current.)

  30. Each of the figures shown is the source of a magnetic field. In which figure does the magnetic dipole vector point in the direction of the negative x axis? (Note: in C and D the arrows show the direction of the current.)

  31. The sketch shows a circular coil in the xz plane carrying a current I. The direction of the magnetic field at point O is • +x • –x • +y • –y • –z

  32. The sketch shows a circular coil in the xz plane carrying a current I. The direction of the magnetic field at point O is • +x • –x • +y • –y • –z

  33. In a circular loop of wire lying on a horizontal floor, the current is constant and, to a person looking downward, has a clockwise direction. The accompanying magnetic field at the center of the circle is directed • horizontally and to the east. • horizontally and to the north. • vertically upward. • parallel to the floor. • vertically downward.

  34. In a circular loop of wire lying on a horizontal floor, the current is constant and, to a person looking downward, has a clockwise direction. The accompanying magnetic field at the center of the circle is directed • horizontally and to the east. • horizontally and to the north. • vertically upward. • parallel to the floor. • vertically downward.

  35. An electron beam travels counterclockwise in a circle of radius R in the magnetic field produced by the Helmholtz coils as shown. If you increase the current in the Helmholtz coils, the electron beam will • increase its radius. • decrease its radius. • maintain the same radius.

  36. An electron beam travels counterclockwise in a circle of radius R in the magnetic field produced by the Helmholtz coils as shown. If you increase the current in the Helmholtz coils, the electron beam will • increase its radius. • decrease its radius. • maintain the same radius.

  37. Which graph best represents the strength of the magnetic field B between the coils of radius R of a Helmholtz pair as a function of distance along the axis of the pair?

  38. Which graph best represents the strength of the magnetic field B between the coils of radius R of a Helmholtz pair as a function of distance along the axis of the pair?

  39. An electron beam travels counterclockwise in a circle in the magnetic field produced by the Helmholtz coils, as shown. Assuming that the earth's field is downward, one can conclude that • the Helmholtz field equals the earth's field. • the current in the coils moves in the same direction as the electron beam. • the current in the coils moves in the direction opposite to the electron beam. • the Helmholtz field curves in the direction of the electron beam. • the Helmholtz field curves in a direction opposite to the electron beam.

  40. An electron beam travels counterclockwise in a circle in the magnetic field produced by the Helmholtz coils, as shown. Assuming that the earth's field is downward, one can conclude that • the Helmholtz field equals the earth's field. • the current in the coils moves in the same direction as the electron beam. • the current in the coils moves in the direction opposite to the electron beam. • the Helmholtz field curves in the direction of the electron beam. • the Helmholtz field curves in a direction opposite to the electron beam.

  41. 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 • from E to W. • from N to S. • from NE to SW. • from S to N. • from W to E.

  42. 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 • from E to W. • from N to S. • from NE to SW. • from S to N. • from W to E.

  43. The current in a wire along the x axis flows in the positive x direction. If a proton, located as shown in the figure, has an initial velocity in the positive z direction, it experiences • a force in the direction of positive x. • a force in the direction of negative x. • a force in the direction of positive z. • a force in the direction of positive y. • no force.

  44. The current in a wire along the x axis flows in the positive x direction. If a proton, located as shown in the figure, has an initial velocity in the positive z direction, it experiences • a force in the direction of positive x. • a force in the direction of negative x. • a force in the direction of positive z. • a force in the direction of positive y. • no force.

  45. A long conductor carrying current I lies in the xz plane parallel to the z axis. The current travels in the negative z direction, as shown in the figure. The vector that represents the magnetic field at the origin O is

  46. A long conductor carrying current I lies in the xz plane parallel to the z axis. The current travels in the negative z direction, as shown in the figure. The vector that represents the magnetic field at the origin O is

  47. Two straight wires perpendicular to the plane of this page are shown in the figure. The currents in the wires are the same. The current in M is into the page and the current in N is out of the page. The vector that represents the resultant magnetic field at point P is

  48. Two straight wires perpendicular to the plane of this page are shown in the figure. The currents in the wires are the same. The current in M is into the page and the current in N is out of the page. The vector that represents the resultant magnetic field at point P is

  49. Current-carrying wires are located along two edges of a cube with the directions of the currents as indicated. Which vector indicates the resultant magnetic field at the corner of the cube?

  50. Current-carrying wires are located along two edges of a cube with the directions of the currents as indicated. Which vector indicates the resultant magnetic field at the corner of the cube?

More Related