1. Figure 22-1 The Force Between Two Bar Magnets

2. Figure 22-2 Magnets Always Have Two Poles

3. A magnet creates a magnetic field in its vicinity.
Magnetism
Magnetic field-
A magnet creates a magnetic field in its vicinity.

4. Magnetism
It represents the effect a magnet has on its surroundings.

5. Magnetism
All magnetic fields arise from the motion of electric charge.

6. Magnetism
A magnetic field is represented by the symbol

7. Magnetism
Magnetic field lines can be used to represent magnetic fields.
The closer the lines are together, the greater the magnitude of the vector

8. Figure 22-4 Magnetic Field Lines for a Bar Magnet

9. The direction of a magnetic field
Magnetism
The direction of a magnetic field
at a given location is the direction in which the north pole of a compass points when it is placed in that location.

10. Figure 22-7 The Magnetic Force on a Moving Charged Particle

11. Example 22-1 A Tale of Two Charges

12. Magnetism
A charged particle moving in a magnetic field will experience a force if it has a velocity component perpendicular to the magnetic field.

13. Magnetism

14. The Magnetic Force Right Hand Rule (RHR)
Magnetism
The Magnetic Force Right Hand Rule (RHR)

15. Magnetism

16. Figure 22-8 The Magnetic Force Right-Hand Rule

17. Figure 22-9 The Magnetic Force for Positive and Negative Charges

18. Conceptual Checkpoint 22-2 Which is the positive? Negative? Zero charge?

19. Magnetism
A charged particle moving with a velocity perpendicular to a uniform magnetic field, will move in a circle.

20. Magnetism
Forces on a long straight current carrying wire in a magnetic field.

21. Magnetism
Forces on a long straight current carrying wire in a magnetic field.

22. Magnetism
A long straight current carrying wire has charges moving inside it.

23. Magnetism
If it is placed in a magnetic field, it will experience a force

24. Magnetism

25. Magnetism

26. Figure 22-15 The Magnetic Force on a Current-Carrying Wire

27. Magnetism
Direction of magnetic forces in a current carrying loop in a magnetic field.

28. Figure 22-16 Magnetic Forces on a Current Loop

29. Example 22-5 Torque on a Coil

30. Magnetism

31. Magnetism

32. Magnetism
To calculate the magnitude and direction of the magnetic field in the vicinity of a long straight current carrying wire.

33. Magnetism Apply the magnetic field right hand rule.
Point your thumb in the direction of current flow.
Curl your fingers around the wire
They will point in the direction of the magnetic field.

34. Figure 22-19 The Magnetic Field of a Current-Carrying Wire

35. Magnetism

36. The number of magnetic field lines that cross an area.
Magnetism
Magnetic flux
The number of magnetic field lines that cross an area.

37. Figure 23-3 The Magnetic Flux Through a Loop

38. Example 23-1 A System in Flux

39. Magnetism
Magnetic flux

40. Magnetism
Faraday’s Law

41. Conceptual Checkpoint 23-1 Which flux(es) change(s) with time?

42. Magnetism
Lenz’s Law
An induced current flows in a direction that opposes the change that caused the current.

43. Conceptual Checkpoint 23-2 How do the accelerations compare?