CONTENT OBJECTIVE: 4B1.00 To understand the principles of conduction
INSTRUCTIONAL OBJECTIVES: The learner will:
1.01 recall the properties of conductors of electricity.
1.02 recall the properties of insulators of electricity.
1.03 formulate a principle for conduction of electricity.
OUTLINE OF CONTENT:
I. Properties of insulators
II. Properties of conductors
III. Principle for conduction
TN COMPONENT OF SCIENCE: Process Of Science
To enable students to demonstrate the process of science by posing questions and investigating phenomena through language, methods and instruments of science
1.5 EXPLAINING - Phenomena and related information are made understandable through discussion that culminates in a higher level of learning
TN STANDARD(S): The learner will understand that:
1.5c Information should be related to prior knowledge.
BENCHMARK: The process of making predictions, drawing inferences, and developing conclusions is based upon an individual's prior learning and understanding of scientific principles..
Dry cell batteries, copper wire, paper, yarn, nail, aluminum foil, paper clip, flashlight bulbs, bulb holders, transparencies (see Instruction), rubber band, paper
(Show an extension cord.) How does electricity get from one end to the other? (It travels through the wire.) Today you will learn the properties of conductors of electricity, the properties of insulators and the principle for conduction of electricity.
We have learned that atoms are the tiniest part of something. They are in everything, including electricity. In electricity there are electrons. The flow of these electrons helps produce electricity. Electricity must have a source. There must be a flow of the electricity from the source of the object that needs energy. If electricity can naturally flow through a certain kind of matter, then that matter is called a CONDUCTOR of electricity.
The atoms in a good conductor of electricity do not have a very tight hold on some of the electrons so these electrons can flow freely through that material. If electricity cannot flow naturally through a certain kind of matter, then that matter is called an INSULATOR. The atoms of an insulator of electricity have such a tight hold on their electrons that few, if any, flow through the material. Electricity will flow through materials which have atoms loosely holding some of their electrons. Metals, such as copper, silver and aluminum, are good conductors of electric current because electricity flows through them easily. Air is an insulator; so are paper, wood and plastic. Why are insulators important on wires? (response)
(Have a flashlight, bulb, bulb holder, a dry cell batter, two wires and tape and a variety of materials. Screw the bulb into the bulb holder. Place one wire on the positive terminal and one on the negative terminal. Touch the loose ends of the wire to the screw on one side of the bulb holder and fasten the loose end to the other screw. ) We have built an electrical circuit. Predict which objects will light the bulb. Test your predictions. Which are conductors? What materials make the best conductors? Now, let's break the wire (Or circuit) and insert different materials. If the bulb lights up, we have a conductor. If it does not, we have an insulator.
Provide students with four index cards. On each of two cards, have students write conductor; on the other two write insulator. Write on the chalkboard the terms conductor and insulator. Ask students to classify objects (teacher or student suggested) on their cards by taking turns patterning sentences. (example, This ruler is an insulator because it is made of wood.
This is the
time this file has been accessed since 07/01/97.
The University of Tennessee at Martin is not responsible for the information or views expressed here.