| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.10 |
| Score | 0% | 62% |
The valence shell of a semiconductor is how full of electrons?
half full |
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more than half full |
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empty |
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less than half full |
Semiconductors have valence shells that are exacly half full and can conduct electricity under some conditions but not others. This property makes them useful for the control of electrical current.
Why is an insulator a poor conductor of electricity?
an insulator is made of organic material |
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an insulator is made of inorganic material |
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an insulator has few free electrons |
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an insulator has many free electrons |
Insulators have valence shells that are more than half full of electrons and, as such, are tightly bound to the nucleus and difficult to move from one atom to another.
Which of the following is not a terminal on a transistor?
input |
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collector |
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base |
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emitter |
A transistor works by allowing a small amount of current applied at the base to control general current flow from collector to emitter through the transistor.
This circuit component symbol represents a(n):
transformer |
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diode |
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transistor |
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inductor |
The transistor is the foundation of modern electronic devices. It is made entirely from semiconductor material (making it a solid state device) and can serve many different functions in a circuit including acting as a switch, amplifier, or current regulator. A transistor works by allowing a small amount of current applied at the base to control general current flow from collector to emitter through the transistor.
In electrical wiring, which of the following are proportional?
the length of the wire and the amount of the voltage |
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the diameter of the wire and the amount of the current |
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the length of the wire and the amount of the current |
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the diameter of the wire and the amount of the voltage |
Current flow through a wire increases the temperature of the wire. If too small a wire is used, the wire will heat up causing a loss in conductivity and possibly a fire. The thicker in diameter a wire is, the more current it can carry without overheating.