| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.26 |
| Score | 0% | 65% |
What is the potential difference in an electrical circuit a measure of?
the load at a specific location in the circuit |
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the current at a specific location in the circuit |
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the resistance at a specific location in the circuit |
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the voltage at a specific location in the circuit |
Electrons flow from an area of high concentration to an area of low concentration. A high voltage indicates a high concentration of electrons that creates a greater potential for electron flow than a low voltage. When applied to a load, voltage creates electricity and potential difference is the measure of voltage at a specific location in an electrical circuit.
Why does current in an electric circuit create heat?
current is naturally hot |
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the wire in the circuit burns when current passes through |
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heat is created when the current overcomes resistance in the wire |
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voltage is naturally hot |
Current in an electric circuit creates heat when the current overcomes resistance in the wire.
Why is an insulator a poor conductor of electricity?
an insulator has few free electrons |
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an insulator has many free electrons |
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an insulator is made of organic material |
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an insulator is made of inorganic material |
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.
| 90 Ω | |
| 45 Ω | |
| 91.5 Ω | |
| 30 Ω |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
Solved for resistance, R = \( \frac{V}{I} \) = \( \frac{720}{8} \) = 90 Ω
Which of the following is not true about a line drop?
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 |
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it is a decrease in voltage between two points on a 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.