| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.82 |
| Score | 0% | 76% |
The conductivity of an element depends on how many electrons occupy which electron shell?
outer |
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inner |
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middle |
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first |
All electricity is the movement of electrons which are subatomic particles that orbit the nucleus of an atom. Electrons occupy various energy levels called shells and how well an element enables the flow of electrons depends on how many electrons occupy its outer (valence) electron shell.
Which of the following allows current to pass easily in one direction and blocks current in the other direction?
diode |
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inductor |
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resistor |
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capacitor |
A diode allows current to pass easily in one direction and blocks current in the other direction. Diodes are commonly used for rectification which is the conversion of alternating current (AC) into direct current (DC). Because a diode only allows current flow in one direction, it will pass either the upper or lower half of AC waves (half-wave rectification) creating pulsating DC. Multiple diodes can be connected together to utilize both halves of the AC signal in full-wave rectification.
Why does current in an electric circuit create heat?
current is naturally hot |
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heat is created when the current overcomes resistance in the wire |
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the wire in the circuit burns when current passes through |
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voltage is naturally hot |
Current in an electric circuit creates heat when the current overcomes resistance in the wire.
All electricity is the movement of which subatomic particles?
nuclei |
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protons |
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electrons |
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neutrons |
All electricity is the movement of electrons which are subatomic particles that orbit the nucleus of an atom. Electrons occupy various energy levels called shells and how well an element enables the flow of electrons depends on how many electrons occupy its outer (valence) electron shell.
Capacitors store:
current |
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electricity |
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capacitance |
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resistance |
Capacitors store electricity and are used in circuits as temporary batteries. Capacitors are charged by DC current (AC current passes through a capacitor) and that stored charge can later be dissipated into the circuit as needed. Capacitors are often used to maintain power within a system when it is disconnected from its primary power source or to smooth out or filter voltage within a circuit.