| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.42 |
| Score | 0% | 68% |
From what energy do photovoltaic cells produce electrical energy?
chemical |
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nuclear |
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magnetic |
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sun |
A photovoltaic cell (also known as a solar cell) converts energy from the sun into electrical energy.
The volt is a unit of measurement for:
capacitance |
|
voltage |
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current |
|
power |
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.
One of the lights on your Christmas tree burns out and this causes the rest of the lights connected to that strand to go dark. How are the lights in that strand connected?
series |
|
perpendicular |
|
parallel |
|
series-parallel |
Lights connected in series form a chain with each light connecting to adjacent lights via one wire. Therefore, if one of the lights burns out and breaks the series, none of the other lights will receive power and they'll go dark. Lights connected in parallel each connect to the positive and negative nodes of the power source and would not go dark if one of their neighbors burnt out.
Which of the following is not a terminal on a transistor?
input |
|
base |
|
collector |
|
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.
In a series circuit, which of the following is the same across all branches of the circuit?
current |
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conductance |
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resistance |
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voltage |
A series circuit has only one path for current to flow. In a series circuit, current (I) is the same throughout the circuit and is equal to the total voltage (V) applied to the circuit divided by the total resistance (R) of the loads in the circuit. The sum of the voltage drops across each resistor in the circuit will equal the total voltage applied to the circuit.