Circuits containing multiple elements Series and parallel combinations RC circuits

1. Chapter 23 Circuits • Circuits containing multiple elements • Series and parallel combinations • RC circuits • Electricity in the nervous system Topics: Sample question: An electric eel can develop a potential difference of over 600 V. How do the cells of the electric eel’s body generate such a large potential difference? Slide 23-1

2. Reading Quiz • The bulbs in the circuit below are connected_________. • in series • in parallel Slide 23-2

3. Answer • The bulbs in the circuit below are connected_________. B. in parallel Slide 23-3

4. Reading Quiz • When three resistors are combined in series the total resistance of the combination is • greater than any of the individual resistance values. • less than any of the individual resistance values. • the average of the individual resistance values. Slide 23-6

5. Answer • When three resistors are combined in series the total resistance of the combination is • greater than any of the individual resistance values. Slide 23-7

6. Drawing Circuit Diagrams Slide 23-8

7. Checking Understanding The following circuit has a battery, two capacitors and a resistor. Which of the following circuit diagrams is the best representation of the above circuit? Slide 23-9

8. Answer The following circuit has a battery, two capacitors and a resistor. Which of the following circuit diagrams is the best representation of the above circuit? Slide 23-10

9. Kirchhoff’s Laws Slide 23-11

10. Using Kirchhoff’s Laws Slide 23-12

11. Clicker Question • The diagram below shows a segment of a circuit. What is the current in the 200 resistor? • 0.5 A • 1.0 A • 1.5 A • 2.0 A • There is not enough information to decide. Slide 23-13

12. Answer • The diagram below shows a segment of a circuit. What is the current in the 200 resistor? B. 1.0 A Slide 23-14

13. Clicker Question • The diagram below shows a circuit with two batteries and three resistors. What is the potential difference across the 200 resistor? • 2.0 V • 3.0 V • 4.5 V • 7.5 V • There is not enough information to decide. Slide 23-15

14. Answer • The diagram below shows a circuit with two batteries and three resistors. What is the potential difference across the 200 resistor? • 2.0 V Slide 23-16

15. Series Resistors Slide 23-17

16. Parallel Resistors Slide 23-18

17. There is a current of 1.0 A in the circuit below. What is the resistance of the unknown circuit element? What is the current out of the battery? Slide 23-19

18. Example Problem In the circuit shown below, rank in order, from most to least bright, the brightness of bulbs A–E. Explain. Slide 23-42

19. Example Problem • In the circuit shown below: • Rank in order, from most to least bright, the brightness of bulbs A–D. Explain. • Describe what, if anything, happens to the brightness of bulbs A, B, and D if bulb C is removed from its socket. Explain. Slide 23-41

20. Example Problem • Compare the brightness of a 40 W bulb and a 25 W bulb • Which would be brighter in parallel? • Which would be brighter in series? • The 25 W bulb • The 40 W bulb • They are equally bright Slide 23-41

21. Analyzing Complex Circuits Slide 23-20

22. What is the equivalent resistance of the following circuit? Find the current in and the potential difference across each element in the following circuit. Slide 23-21

23. Household Electricity Slide 23-22

24. The following devices are plugged in to outlets on the same 120 V circuit in a house. This circuit is protected with a 15 A circuit breaker. Device Power Computer 250 W Heater 900 W Lamp 100 W Stereo 120 W Is there too much current in the circuit—does the circuit breaker blow? Slide 23-23