Why don't electronics care if it's DC or AC current?

In summary, AC is used for transportation due to its economic benefits and ease of production from converting mechanical energy into electrical energy. However, in electronics, AC power is converted to DC power so that the electronics can function without interruption. Some components, like transformers and capacitors, only work with AC power, while others, like computers, are designed to work with DC power. It is not recommended to modify a computer power supply for other purposes as it can be dangerous. A cheap lab power supply or a 9V battery snap can be used for experimentation with basic electronic components.
  • #1
calvinjhfeng
32
0
I understand AC is economic for transportation and easy to produce from converting mechanical energy into electrical energy.

However, why don't electronics turn on and off because of this alternating nature of the current? For light bulb, maybe it does turn on and off and our eyes don't have fast enough *shutter speed* to capture the off moment so we are just seeing the average brightness of the light bulb.

But what about computers? They did something to the battery so it doesn't turn off when current reaches its 0 point?
 
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  • #2
An incandescent light turns on and off 120 times a second (the polarity reverses at double the operating frequency. The filiment doesn't have time to cool off so we don't "see" the flicker.
In electronics (like your computer) the power supply converts the AC to DC so the electronics can do their job in an uninterupted flow.
 
  • #3
This is puzzling. What makes you think electronics "don't care"?

I have a power adapter that converts the household AC into a 12V DC for one of my "electronics". This is an obvious example that it DOES matter if it is AC or DC for some components!

Zz.
 
  • #4
Some electronics do care about AC or DC.

Transformers only work on AC power.

Capacitors block DC but will allow an AC current to pass (also the frequency of the AC is important as a higher frequency passes through more easily)
 
  • #5
Ahh I see, thank you.

So are all computer power units have DC output? Can I modify the connection so I can use it as a power source to let's say charge a capacitor?
 
  • #6
calvinjhfeng said:
Ahh I see, thank you.

So are all computer power units have DC output? Can I modify the connection so I can use it as a power source to let's say charge a capacitor?

I wouldn't recommend modifying the power supply in your pc as it could be very dangerous due to the voltages involved and the fact you are using it for a purpose that it obvoiusly was never intended.

If you wish to experiment with some basic electronic components you would be better off getting a cheap lab power supply as these will provide a safe source of power and are fused in case of any faults that may occur.

If you can't get a lab power supply then you could use a battery snap to connect a 9V PP3 battery and that should be adequate for most small electronics circuits.
 

1. Why do electronic devices work with both DC and AC current?

This is because electronic devices are designed to convert AC current into DC current. AC current is the type of electricity that is supplied by power plants and travels through power lines. However, most electronic devices, such as smartphones and laptops, require DC current to function. Therefore, they have built-in components, such as rectifiers and capacitors, that convert AC current into DC current.

2. Can I use DC power to power an AC device, or vice versa?

Yes, you can use DC power to power an AC device, but you will need to use a device called an inverter to convert the DC current into AC current. Similarly, you can use AC power to power a DC device, but you will need a device called a rectifier to convert the AC current into DC current.

3. Is one type of current better for electronic devices?

No, both DC and AC current have their own advantages and disadvantages. For example, DC current is better for powering small devices because it is more efficient and can be easily regulated. On the other hand, AC current is better for long-distance power transmission because it can travel over longer distances without significant power loss.

4. Can DC and AC current be used together in an electronic circuit?

Yes, DC and AC current can be used together in an electronic circuit. In fact, many electronic devices, such as radios and televisions, use both DC and AC current in their circuits. The AC current is used for the power source, while the DC current is used to power specific components within the device.

5. Are there any safety concerns with using DC and AC current in electronic devices?

Yes, there are safety concerns when handling both DC and AC current, as they can both be dangerous if not handled properly. AC current, in particular, can cause electric shock at higher voltages. It is important to always follow safety precautions and guidelines when working with electricity, regardless of the type of current.

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