Schematic Diagrams of Circuits: Symbols

*Copy Table 20-1 page 731

Symbol Conventions for Circuits.Schematic

map keys for electronic components.

emf The source of potential difference and electrical

energy is the circuit emf. (ie. Battery or outlet)The emf is the energy per unit charge supplied by

a source of electric current. (ie. Charge Pump)The terminal voltage is actually slightly less than

the emf. Unless otherwise stated , any reference in this book to potential difference across a battery should be thought of as the potential difference measured across the battery terminals. (ie. Potential difference across a load equals the terminal voltage.)

Resistors in Series Circuits

Resistors in SeriesPage 737 Figure 20-11

Req = R1 + R2 + R3 …

Equivalent resistance equals the total individual resistances in series

*Example 20A page 738

Resistors in Parallel Circuits

Resistors in ParallelPage 741-742 Fig. 20-14

1 = 1 + 1 + 1 Req R1 R2 R3

Equivalent resistance of resistors in parallel can be calculated

using a reciprocal relationship

* Example 20B page 743

Homework Chp. 20 Chp. 20 BK

20A 1- 4 2. a. 24Ω b. 1A c. C.1A 4. a) 11.28 Ω =Req I= .798 A

b) V= 5.79 V V= 3.22 V

• 20B 1,3,4 4. a) 2.99Ω b)36V c)2A= I 6A=I3

Chp. 20 WKBK 20A 1,2,4,5 1. 2000 kΩ 2. 4.1 x 108 Ω

4. V= 20000 V 5. R 12 =8.5 Ω

R13 = 20.5 Ω

R23 = 20 Ω

• 20B 1,4 1. Req = 1.3 Ω 4. R= .1Ω