1. Simple AC Motors J Pemberton

2. Best Website on This! http://www.physclips.unsw.edu.au/jw/electr icmotors.html http://www.physclips.unsw.edu.au/jw/electr icmotors.html

3. There are two main types Synchronous- a magnet or current carrying coil moving due to a changing magnetic field. Induction- a piece of metal in a changing magnetic field has currents set up in it which then experience a force.

4. Simplest AC Motor To understand this we have to revise the field directions for solenoids. Check you agree with the next few slides

5. Simple AC Motor- first part of cycle N S Look closely at the current directions, Do you agree with the field directions?

6. Simple AC Motor- Make your predictions for the second half of cycle

7. Simple AC Motor- Second half of cycle? N S

8. The north pole will seek out the south poles of the solenoid and visa versa.

9. Simple AC Motor- Now with the magnet N S Which way will the magnet want to go?

10. Simple AC Motor- first part of cycle N S Did you guess correctly?

11. Simple AC Motor- Second half of cycle The field gets switched. N S

12. N S

13. N S

14. Simple AC Motor- Now were back to the beginning. N S Which way will the magnet want to go?

15. Simple AC Motor- An off we go! N S Which way will the magnet want to go?

16. Simple AC Motor- Second half of cycle The field gets switched. N S

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18. N S

19. N S

20. Simple AC Motor- Now were back to the beginning. N S Which way will the magnet want to go?

21. Simple AC Motor- Now were back to the beginning. N S Which way will the magnet want to go?

22. Simple AC Motor- Now were back to the beginning. N S Which way will the magnet want to go?

23. Simple AC Motor- Now were back to the beginning. N S Which way will the magnet want to go?

24. Simple AC Motor- Second half of cycle The field gets switched. N S

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27. N S

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31. AC motors often have more than two solenoids

32. Simple AC Motor- four coils N S S N

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44. N S