| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.50 |
| Score | 0% | 70% |
A capacitor is often used for which of the following purposes?
to convert alternating current into direct current |
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to maintain power in a circuit when the primary power source is disconnected |
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as a primary power source |
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to allow a small amount of current to control a large amount of current |
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.
Current is the rate of flow of electrons per unit time and is measured in:
volts |
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ohms |
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coulombs |
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amperes |
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.
The formula specifying Ohm's law is which of the following?
V = I2R |
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\(V = {I \over R}\) |
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\(V = {R \over I}\) |
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V = IR |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
This circuit diagram represents a(n):
open circuit |
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parallel circuit |
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series circuit |
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series-parallel circuit |
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.
A diode to an electronic circuit is like a _______________ to a city?
highway |
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one-way street |
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traffic light |
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parking lot |
A diode allows current to pass easily in one direction and blocks current in the other direction.