| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
Which of the following allows DC to pass easily but resists the flow of AC?
capacitor |
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semiconductor |
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inductor |
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transformer |
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.
This circuit component symbol represents a(n):
fuse |
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potentiometer |
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inductor |
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transformer |
Resistors are used to limit voltage and/or current in a circuit and can have a fixed or variable resistance. Variable resistors (often called potentiometers or rheostats) are used when dynamic control over the voltage/current in a circuit is needed, for example, in a light dimmer or volume control.
Which of the following is a characteristic of batteries connected in series?
total voltage equals the average of the individual battery voltages |
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total voltage equals the sum of the individual battery voltages |
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two connections are made between each adjacent battery |
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the positive terminal of one battery is connected to the positive terminal of the next |
You can multiply the voltage or the current supplied by individual batteries by connecting them together either in series or in parallel. The characteristics of batteries connected in series are that total voltage equals the sum of the individual battery voltages, total current equals the average of the individual battery currents, the positive terminal of one battery is connected to the negative terminal of the next, and one connection is made between each adjacent battery.
| 3.15 A | |
| 7 A | |
| 3.5 A | |
| 5.25 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 = \( \frac{V}{R} \) = \( \frac{35}{10} \) = 3.5 A
Voltage and current are __________ proportional.
inversely |
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not |
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directly |
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indirectly |
Voltage (V) is the electrical potential difference between two points. Electrons will flow as current from areas of high potential (concentration of electrons) to areas of low potential. Voltage and current are directly proportional in that the higher the voltage applied to a conductor the higher the current that will result.