| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.54 |
| Score | 0% | 71% |
| 95 Ω | |
| 90 Ω | |
| 270 Ω | |
| 93 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 = \( \frac{V}{I} \) = \( \frac{585}{6.5} \) = 90 Ω
A capacitor is often used for which of the following purposes?
to allow a small amount of current to control a large amount of current |
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as a primary power source |
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to convert alternating current into direct current |
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to maintain power in a circuit when the primary power source is disconnected |
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.
The most common circuit configuration is:
series |
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parallel |
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household |
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series-parallel |
Circuits are not limited to only series or only parallel configurations. Most circuits contain a mix of series and parallel segments. A good example is a household circuit breaker. Electrical outlets in each section of the house are wired in parallel with the circuit breaker for that section wired in series making it easy to cut off electricity to the parallel parts of the circuit when needed.
The ampere is a unit of measurement for:
current |
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energy |
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inductance |
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power |
Current is the rate of flow of electrons per unit time and is measured in amperes (A). A coulomb (C) is the quantity of electricity conveyed in one second by a current of one ampere.
Capacitors store:
current |
|
capacitance |
|
resistance |
|
electricity |
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.