Lesson 2

Getting Down To Basics

Objectives:

When the students have finished this chapter they should be able to answer questions on the basic concepts of:

Apparatus:

  1. primary and secondary cells

  2. clip leads

  3. resistors of various types
    (old circuit boards with resistors are useful)

  4. samples of conductors and non-conductors

  5. measuring and monitoring equipment

  6. horseshoe and bar magnets and iron filings
    (you probably could borrow these from the Science Department of your local high school)

Handouts:

Lesson Plan:

  1. Answer any questions about the homework, especially those dealing with math skills

  2. Use a VOM to demonstrate conductivity and how to identify conductors versus insulators. Encourage your students to invest in an inexpensive VOM.

  3. Use a VOM to show how to measure resistance. Have students determine resistance of resistors.

  4. Have students determine the resistance and tolerance of resistors from the colour codes. You may have to review using percentages.

  5. The lines of magnetic force can be demonstrated by putting a bar magnet under a piece of paper and scattering iron filings on the paper above the magnet.

  6. Demonstrate the use of the VOM to measure DC. Have the students measure the voltages of various cells.

  7. Use cells and clip leads to demonstrate the voltage of cells arranged in series and in parallel.

  8. Use a coil, horseshoe magnet and an ammeter to show that a flow of current is generated when a coil is moved through a magnetic field, a magnetic field is moved around a coil, and a combination of both.

  9. Use an oscilloscope to show an AC waveform. This is an ideal opportunity to introduce the terms frequency, wave length, and amplitude. Show waves of different frequencies.

  10. Demonstrate the use of the VOM to measure AC.

Homework:

  1. Read the rest of Chapter 2.

  2. Do the Chapter 2 Quiz.

  3. Skim Chapter 3.

Chapter 2 Quiz

Printable copy of the Review Quiz

Answers to Chapter 2 Quiz.
1 B 9 A 17 D 25 B 33 A
2 C 10 B 18 A 26 C 34 A
3 D 11 A 19 B 27 C 35 A
4 D 12 C 20 C 28 B 36 D
5 A 13 B 21 A 29 A 37 A
6 D 14 D 22 D 30 D 38 D
7 B 15 A 23 D 31 A 39 B
8 A 16 A 24 B 32 D * *

Overhead Slide Versions of the Diagrams

  1. Slide 1
    2.1 Hydrogen Atom
    2.2 Helium Atom
    2.3 Copper Atom

  2. Slide 2
    2.4 Current Flow in a Conductor

  3. Slide 3
    2.6 The Resistor Colour Code
    2.5 Colour Code Table

  4. Slide 4
    2.9 Direct Current, Graph of current flow
    2.10 Direct Current, Graph of voltage

  5. Slide 5
    2.11 Cells in Parallel, Physical Diagram
    2.12 Cells forming a Battery
    2.13 Cell with a load, physical layout
    2.14Cell with a load, schematic diagram

  6. Slide 6
    2.15 Battery Reversal, Voltage Graph
    2.16 Battery Reversal, Current Graph
    2.17 Alternating Current, conceptual drawing

  7. Slide 7
    2.18 AC half-cycle
    2.19 One cycle of voltage sine wave showing degrees
    2.20 One cycle of Current sine wave showing degrees, (in phase with 2.19)
    2.21 Several sine wave cycles, with names

  8. Slide 8
    2.22 Comparison of power in AC cycle and DC of same duration