5A
YOUR ANSWER:
Yes. Electrons can be made to flow, even in insulators.
(From P1-19B)
Correct. With a sufficient force, electrons will flow in any material. First of all, there is no such thing as
a perfect insulator, so there is always some electron movement. When we apply enough force (voltage) to cause
an intense flow (avalanche) of electrons through an insulator, we have reached the insulator's breakdown point.
The insulator is now acting like a conductor and the result is generally the destruction of the insulator.
Effects of insulator breakdown are burning or charring of combustible material and breaking or cracking
of noncombustible materials. These effects are very obvious, so your nose and your eyes can be valuable tools in
troubleshooting electronics gear.
We have one final item to cover in this lesson. Resistors. No, not resistance, RESISTORS. But before
we get into a discussion on resistors, let's drop back and see what you remember about resistance. Choose the
correct definition for resistance.
Resistance is the opposition
offered to the flow of electrons.
Page 1-7A
Resistance is a measure of the opposition
of a particular volume of material at a
temperature of 20 degrees centigrade.
Page 1-22A
5B
YOUR ANSWER:
The specific resistance of a material is the resistance of a unit volume
(From P1-12B)
of that material at a temperature of 20 degrees centigrade.
Absolutely true BUT what about the other three statements? Aren't they also correct? Perhaps you didn't
bother to read more than the first statement. Go back to Page 1-12B and read the rest of them. See if there isn't a
more correct answer.
1-5
IT0340
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