Chapter U1.25, Problem 2E

Interpretation Introduction

Interpretation : The method to determine whether a substance can conduct electricity or not needs to be described.

Concept Introduction : Conductivity is a general property by which one can sort substances into two categories: conductors and non- conductors. Some substances can allow the flow of electricity through them. Such substances are called conductors. For example, Copper.

Some substances do not allow the flow of electricity through them. Such substances are called non- conductors. For example, plastic.

Explanation of Solution

Some substances such as metals conduct electricity while some like plastic does not conduct electricity. There is a simple way to determine whether a substance conducts electricity or not.

A simple electrical circuit is set up. It consists of a light bulb, a battery and a copper/aluminum wire. The light bulb is connected to the terminals of a battery through a copper wire. When the circuit is complete, there will be a flow of current from the battery to the bulb through the wire and the bulb will glow. Electrical current flows due to the flow of electrons from the negative to the positive terminal of the battery.

If a substance to be tested is connected to the circuit and the bulb glows, it means the testing substance conducts electricity. If the bulb does not glow, it means the circuit is broken due to a non- conductor.

Conclusion

Electrical conductivity is an important property of substances. It helps in understanding the flow of electrons. Metals are good conductors of electricity.