| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.41 |
| Score | 0% | 68% |
Resistance is measured in:
ohms |
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volts |
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amperes |
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coulombs |
Resistance is opposition to the flow of current and is measured in ohms (Ω). One ohm is defined as the amount of resistance that will allow one ampere of current to flow if one volt of voltage is applied. As resistance increases, current decreases as resistance and current are inversely proportional.
The formula specifying Ohm's law is which of the following?
\(V = {I \over R}\) |
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\(V = {R \over I}\) |
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V = I2R |
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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.
What is the voltage of most household electrical systems in the United States?
110V |
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60V |
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60Hz |
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220V |
Most households use electricity with a voltage of 110V.
In household electrical wiring, which color of insulation indicates the 'hot' wire?
green |
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white |
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red |
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black |
In the NM cable used for wiring homes, each cable has three wires inside a sheath with each wire covered in a different color of insulation to indicate its type. The wire with the black insulation is the 'hot' wire, white is the neutral wire, and the ground wire is either covered in green insulation or left bare.
This circuit diagram represents a(n):
series-parallel circuit |
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open circuit |
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series circuit |
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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.