1. Physics for Scientists and Engineers II, Summer Semester 2009 1 Lecture 19: July 8 th 2009 Physics for Scientists and Engineers II

2. Physics for Scientists and Engineers II, Summer Semester 2009 2 RLC Series Circuits –solved using Kirchhoff’s loop

3. Physics for Scientists and Engineers II, Summer Semester 2009 3 RLC Series Circuits –solved using Kirchhoff’s loop

4. Physics for Scientists and Engineers II, Summer Semester 2009 4 RLC Series Circuits –solved using Kirchhoff’s loop

5. Physics for Scientists and Engineers II, Summer Semester 2009 5 RLC Series Circuits –solved using Kirchhoff’s loop

6. Physics for Scientists and Engineers II, Summer Semester 2009 6 RLC Series Circuits –solved using Kirchhoff’s loop

7. Physics for Scientists and Engineers II, Summer Semester 2009 7 RLC Series Circuits - book’s method

8. Physics for Scientists and Engineers II, Summer Semester 2009 8 RLC Series Circuits - book’s method

9. Physics for Scientists and Engineers II, Summer Semester 2009 9 Phasor Diagram The voltages across the components are out of phase as shown in the phasor diagram. They need to be added as vectors to get the total voltage.

10. Physics for Scientists and Engineers II, Summer Semester 2009 10 Phasor Diagram The voltages across L and C can simply be subtraced from each other (180 degrees out of phase).

11. Physics for Scientists and Engineers II, Summer Semester 2009 11 Phasor Diagram

12. Physics for Scientists and Engineers II, Summer Semester 2009 12 Power in an AC Circuit

13. Physics for Scientists and Engineers II, Summer Semester 2009 13 Power in an AC Circuit “Power factor”

14. Physics for Scientists and Engineers II, Summer Semester 2009 14 Implications of power factor “Power factor”

15. Physics for Scientists and Engineers II, Summer Semester 2009 15 Resonance in a Series RLC Circuit – the current

16. Physics for Scientists and Engineers II, Summer Semester 2009 16 Resonance in a Series RLC Circuit – the Current

17. Physics for Scientists and Engineers II, Summer Semester 2009 17 Resonance in a Series RLC Circuit – power

18. Physics for Scientists and Engineers II, Summer Semester 2009 18 Resonance in a Series RLC Circuit – power Describes sharpness of resonance. Q is larger for smaller R.

19. Physics for Scientists and Engineers II, Summer Semester 2009 19 AC Transformer – a simple design Primary Winding (input) Secondary Winding (output)

20. Physics for Scientists and Engineers II, Summer Semester 2009 20 AC Transformer - Voltage Transformation

21. Physics for Scientists and Engineers II, Summer Semester 2009 21 Step-up versus Step-down Transformers

22. Physics for Scientists and Engineers II, Summer Semester 2009 22 AC Transformer – Connecting the load rms values

23. Physics for Scientists and Engineers II, Summer Semester 2009 23 Transmission line economics

24. Physics for Scientists and Engineers II, Summer Semester 2009 24 Transmission line economics