| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.75 |
| Score | 0% | 55% |
Which of the following is not true about a line drop?
it is a decrease in voltage between two points on a line |
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it is caused by resistance |
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it is addressed by raising current and lowering voltage across the ransmission line |
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it is addressed by raising voltage and lowering current across the transmission line |
Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances. A line drop is a decrease in voltage between two points on an electrical transmission line due to resistance in the line. A lower current and higher voltage across the line will help compensate for the line drop.
Electromotive force is another name for:
power |
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voltage |
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current |
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energy |
Voltage (V) is the electrical potential difference between two points. Electrons will flow as current from areas of high potential (concentration of electrons) to areas of low potential. Voltage and current are directly proportional in that the higher the voltage applied to a conductor the higher the current that will result.
Which of the following is not an advantage of semiconductors over conductors?
materials to produce semiconductors are cheap and abundant |
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a semiconductor's conductivity can be varied under an external electrical field |
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a semiconductor exhibits increased conductivity with increased temperatures |
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a semiconductor conducts current better than a conductor |
A semiconductor is a material that has a limited ability to conduct electrical current with conductivity between that of an insulator and that of a conductor. Silicon, a cheap and abundant material, is the most used semiconductor material although other materials are used in the electronics components made from semiconductors. The primary advantages of a semiconductor over a conductor is that the conductivity of a semiconductor can be varied under an external electrical field giving engineers precise control over complex circuits and, unlike conductors like metals, a semiconductor's conductivity increases with increased temperatures.
Resistance and current are __________ proportional.
not |
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directly |
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exponentially |
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inversely |
Resistance is opposition to the flow of current and is measured in ohms (Ω). One ohm is defined as the amount of resistance that will allow one ampere of current to flow if one volt of voltage is applied. As resistance increases, current decreases as resistance and current are inversely proportional.
Which of the following is a characteristic of batteries connected in series?
the positive terminal of one battery is connected to the positive terminal of the next |
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total voltage equals the sum of the individual battery voltages |
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total voltage equals the average of the individual battery voltages |
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two connections are made between each adjacent battery |
You can multiply the voltage or the current supplied by individual batteries by connecting them together either in series or in parallel. The characteristics of batteries connected in series are that total voltage equals the sum of the individual battery voltages, total current equals the average of the individual battery currents, the positive terminal of one battery is connected to the negative terminal of the next, and one connection is made between each adjacent battery.