| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.69 |
| Score | 0% | 74% |
This circuit component symbol represents a(n):
transformer |
|
inductor |
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capacitor |
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resistor |
An inductor is coiled wire that stores electric energy in the form of magnetic energy and resists changes in the electric current flowing through it. If current is increasing, the inductor produces a voltage that slows the increase and, if current is decreasing, the magnetic energy in the coil opposes the decrease to keep the current flowing longer. In contrast to capacitors, inductors allow DC to pass easily but resist the flow of AC.
Silver and gold are among the most highly conductive elements. Why is copper used much more often as a conductor in electrical circuits?
all of these |
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copper is durable and relatively cheap |
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silver and gold are brittle |
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silver and gold are costly |
All conductors have resistance and the amount of resistance varies with the element. But, resistance isn't the only consideration when choosing a conductor as the most highly conductive elements like silver and gold are also more expensive and more brittle than slightly less conductive elements like copper. A balance needs to be struck between the electrical qualities of a material and its cost and durability.
Which of the following will help to prevent a short circuit?
fuse |
|
resistor |
|
diode |
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transistor |
Fuses are thin wires that melt when the current in a circuit exceeds a preset amount. They help prevent short circuits from damaging circuit components when an unusually large current is applied to the circuit, either through component failure or spikes in applied voltage.
| 10.5 A | |
| 8.5 A | |
| 7 A | |
| 3.5 A |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
Solved for current, I = \( \frac{V}{R} \) = \( \frac{70}{10} \) = 7 A
Longer the electrical wires mean _______________ voltage drop.
greater |
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lesser |
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diminishing |
|
complete |
Electrical wires have a certain amount of resistance per foot. A longer wire means more resistance and a greater voltage drop.