| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.38 |
| Score | 0% | 68% |
Which of the following statements about a capacitor is false?
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 |
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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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you should always discharge any capacitors before working on an electronic circuit |
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.
Which of the following is a characteristic of batteries connected in series?
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 |
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total voltage equals the average of the individual battery voltages |
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.
Which of the following is a characteristic of batteries connected in parallel?
total current equals the average of the individual battery currents |
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one connection is made between each adjacent battery |
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total current equals the sum of the individual battery currents |
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the positive terminal of one battery is connected to the negative 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 parallel are that total voltage equals the average of the individual battery voltages, total current equals the sum of the individual battery currents, the positive terminal of one battery is connected to the positive terminal of the next, the negative terminal of one battery is connected to the negative terminal of the next, and two connections are made between each adjacent battery.
Which of the following allows encapsulating complex circuit designs for easier integration into electronic devices and machines?
integrated circuits |
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parallel circuits |
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series-parallel circuits |
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series circuits |
Circuits containing transistors are packaged into integrated circuit chips that allow encapsulating complex circuit designs (CPU, memory, I/O) for easier integration into electronic devices and machines.
Silver and gold are among the most highly conductive elements. Why is copper used much more often as a conductor in electrical circuits?
silver and gold are brittle |
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all of these |
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silver and gold are costly |
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copper is durable and relatively cheap |
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.