| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.41 |
| Score | 0% | 68% |
What is the voltage of most household electrical systems in the United States?
60Hz |
|
60V |
|
220V |
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110V |
Most households use electricity with a voltage of 110V.
This circuit component symbol represents a(n):
transistor |
|
AC source |
|
DC source |
|
transformer |
In contrast to the constant one-way flow of direct current, alternating current changes direction many times each second. Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances.
The watt is a unit of measurement for:
power |
|
resistance |
|
frequency |
|
energy |
Electrical power is measured in watts (W) and is calculated by multiplying the voltage (V) applied to a circuit by the resulting current (I) that flows in the circuit: P = IV. In addition to measuring production capacity, power also measures the rate of energy consumption and many loads are rated for their consumption capacity. For example, a 60W lightbulb utilizes 60W of energy to produce the equivalent of 60W of heat and light energy.
The hertz is a unit of measurement for:
power |
|
frequency |
|
inductance |
|
energy |
The hertz is a unit of measurement for frequency.
The valence shell of n insulator is how full of electrons?
less than half full |
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half full |
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more than half full |
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empty |
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.