| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.26 |
| Score | 0% | 65% |
From what energy do photovoltaic cells produce electrical energy?
nuclear |
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sun |
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magnetic |
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chemical |
A photovoltaic cell (also known as a solar cell) converts energy from the sun into electrical energy.
You would measure the amount of resistance at a certain point in a circuit with a(n):
potentiometer |
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voltmeter |
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ohmmeter |
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ammeter |
Resistance is opposition to the flow of current and is measured in ohms (Ω). An ohmmeter is used to measure the amount of resistance at a certain point in a circuit.
Electrons will flow as current from areas of __________ potential (concentration of electrons) to areas of __________ potential.
low, low |
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high, low |
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low, high |
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high, high |
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.
In electrical wiring, which of the following are proportional?
the diameter of the wire and the amount of the voltage |
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the length of the wire and the amount of the voltage |
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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 current |
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.
Which of the following is the same for each branch of a parallel circuit?
current |
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resistance |
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voltage |
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power |
In a parallel circuit, each load occupies a separate parallel path in the circuit and the input voltage is fully applied to each path. Unlike a series circuit where current (I) is the same at all points in the circuit, in a parallel circuit, voltage (V) is the same across each parallel branch of the circuit but current differs in each branch depending on the load (resistance) present.