| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.04 |
| Score | 0% | 61% |
What is the primary difference between a rectifier and an inverter?
a rectifier converts an AC input to DC while an inverter converts a DC input to AC |
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a rectifier converts a DC input to AC while an inverter converts an AC input to DC |
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a rectifier strips out the DC portion of electricity while an inverter strips out the AC portion |
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a rectifier strips out the AC portion of electricity while an inverter strips out the DC portion |
A diode allows current to pass easily in one direction and blocks current in the other direction. Diodes are commonly used for rectification which is the conversion of alternating current (AC) into direct current (DC). Because a diode only allows current flow in one direction, it will pass either the upper or lower half of AC waves (half-wave rectification) creating pulsating DC. Multiple diodes can be connected together to utilize both halves of the AC signal in full-wave rectification.
Which of the following will help to prevent a short circuit?
resistor |
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diode |
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fuse |
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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.
Which of the following statements about a capacitor is false?
you should always discharge any capacitors before working on an electronic circuit |
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to discharge a capacitor safely, use a high-wattage resistor comparable to the capacitance of the capacitor |
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it is safe to touch a capacitor with your hands as long as it is small |
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a capacitor remains charged even after the input voltage is removed |
The purpose of a capacitor is to retain electric charge and it will do so even after its input voltage is removed. After the input voltage is removed, the capacitor will slowly discharge but, depending on the size and characteristics of the capacitor, discharging could take from a few minutes to a few years. So, it's never safe to touch a capacitor with your hands and you should make sure to discharge any capacitors in a circuit before working on it using an appropriately high-wattage resistor or a capacitor discharge tool.
In an electronic circuit, a thermocouple can be used to:
link the temperature of one component in the circuit to that of another component in the circuit |
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increase or decrease the temperature of a component in the circuit |
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keep the circuit at a designated safe temperature |
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open or close a circuit at a designated temperature |
A thermocouple is a temperature sensor that consists of two wires made from different conductors. The junction of these two wires produces a voltage based on the temperature difference between them and can be used like a switch to open or close the circuit at a designated temperature.
What kind of diode allows current to flow in the opposite direction once a certain voltage threshold is reached?
light emitting diode |
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zener diode |
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standard diode |
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v-type diode |
A diode allows current to pass easily in one direction and blocks current in the other direction. A zener diode is a diode which allows current to flow in one direction as normal and will also allow current flow in the reverse direction when the voltage is above a certain value. This value is called the breakdown voltage.