19A
YOUR ANSWER:
There are three types and two classifications of resistors.
(From P1-29A)
I'm afraid you are a little confused. Let's try it again. There are two types of resistors. They are metallic
and nonmetallic. There are three classifications of resistors. They are fixed, tapped, and variable resistors. Now
go back to Page 1-29A and try it again.
19B
YOUR ANSWER:
All the above statements are correct.
(From P1-12B)
Perfect. You have learned everything we have covered so far. But don't pat yourself on the back yet,
because we still have more to cover. We now have conductors, with their electrons galloping along through them,
but what happens when a conductor touches something it isn't supposed to? Like the ground, or maybe you? If it
happens to be you, it results in electrons leaving the conductor and traveling through you to ground. This results
in a little effect called electrical shock. As you already know, this can be fatal, so we need something to isolate
our conductors. We do this with insulators.
An electrical insulator is a material which is very reluctant to permit electron flow. An insulator has
electrons just as all materials have, but it has practically no free electrons. The valence electrons have combined
with other valence electrons to complete the valence shell, leaving virtually no free electrons available. Hard
rubber, glass, bakelite, porcelain, varnished fabric, dry air, oil, and mica are examples of good insulating
materials.
Do you think it is possible to cause electron flow, even in an insulator?
Yes.
Page 1-5A
No.
Page 1-11A
1-19
IT0340
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