1. Chapter 27 Circuits In this chapter we will cover the following topics: -Electromotive force (emf) -Ideal and real emf devices -Kirchhoff’s loop rule -Kirchhoff’s junction rule -Multiloop circuits -Resistors in series -Resistors in parallel -RC circuits, charging and discharging of a capacitor (27 – 1)

2. A cylindrical copper rod has resistance R. It is reformed to three times its original length with no change of volume. Its new resistance is: A. R B. 3R C. 9R D. R/9 E. R/3

3. pump High (+) reservoir Low (-) reservoir (27 – 2)

4. (27 – 3)

5. V i Ideal emf device V i Real emf device (27 – 4)

6. (27 – 5)

7. R i motion R i + - + - (27 – 6)

8. (27 – 7)

9. (27 – 8)

10. i V (27 – 9)

11. (27 – 10)

12. (27 – 11)

13. (27 – 12)

14. (27 – 13)

15. (27 – 14)

16. + - i (27 – 15)

17. (27 – 16)

18. + - i q t qoqo O (27 – 17)

19. In the diagram R1 > R2 > R3. Rank the three resistors according to the current in them, least to greatest. A. 1, 2, 3 B. 3, 2, 1 C. 1, 3, 2 D. 3, 1, 3 E. All are the same

20. A. 5 ΩB. 7 ΩC. 2 ΩD. 11 ΩE. NOT

21. I. In the diagram, the current in the 3-resistor is 4A. The potential difference between points 1 and 2 is: A. 0.75V B. 0.8V C. 1.25V D. 12V E. 20V