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Q35. What is the greatest threat to a diode?
Q36. When checking a diode with an ohmmeter, what is indicated by two high resistance
measurements?
SUMMARY
Now that we have completed this chapter, a short review of the more important points covered in the
chapter will follow. You should be thoroughly familiar with these points before continuing on to chapter
2.
The UNIVERSE consists of two main parts-matter and energy.
MATTER is anything that occupies space and has weight. Rocks, water, and air are examples of
matter. Matter may be found in any one of three states: solid, liquid and gaseous. It can also be composed
of either an element or a combination of elements.
An ELEMENT is a substance that cannot be reduced to a simpler form by chemical means. Iron,
gold, silver, copper, and oxygen are all good examples of elements.
A COMPOUND is a chemical combination of two or more elements. Water, table salt, ethyl
alcohol, and ammonia are all examples of compounds.
A MOLECULE is the smallest part of a compound that has all the characteristics of the compound.
Each molecule contains some of the atoms of each of the elements forming the compound.
The ATOM is the smallest particle into which an element can be broken down and still retain all its
original properties. An atom is made up of electrons, protons, and neutrons. The number and arrangement
of these particles determine the kind of element.
An ELECTRON carries a small negative charge of electricity.
The PROTON carries a positive charge of electricity that is equal and opposite to the charge of the
electron. However, the mass of the proton is approximately 1,837 times that of the electron.
