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Questions tagged [electronics]

Electronics is the study of electric circuits and electrical components, and the design of useful devices. Some questions in this tag may be more appropriate for the [Electrical Engineering(https://electronics.stackexchange.com/) SE site.

Books and Introductory Kits

Many American Universities teach an introductory course in electronics based on the book The Art of Electronics and its accompanying Student Manual. The resulting course is lab-oriented. For physicists not affiliated with a university, Make Magazine's Electronics manual and the accompanying components kits (1,2) provide an easier way to purchase the necessary components, but the resulting curriculum is more electrical engineering oriented.

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Is there a physical limit to data transfer rate?

Is there a physical limit to data transfer rate (e.g. for USB $3.0$, this rate can be a few Gbit per second)? I am wondering if there is a physical law giving a fundamental limit to data transfer rate, similar to how the second law of thermodynamics…
Shing
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How do headphones and earphones produce good bass if tiny speakers can't produce low frequency sounds very well?

It's a well known fact that small/tiny speakers cannot produce low frequency sounds very well. Conversely, large speakers cannot produce high frequency sounds very well. Hence the need for tweeters and woofers in your speaker systems. But, how do…
navigator
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Why can't you hear music well over a telephone line?

Why can't you hear music well well over a telephone line? I was asked this question in an interview for a university study placement and I unfortunately had no idea. I was given the hint that the telephone sampling rate is 8000 samples per second.
Danny Rancher
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How is data transferred between devices?

If you send a text from your phone to your friend, do electrons move from your phone to your friend's phone? How is text transferred (physics wise)? I am a programmer and I want to know how it is working.
Adm Kuznetsov
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How does power consumption vary with the processor frequency in a typical computer?

I am looking for an estimate on the relationship between the rate of increase of power usage as the frequency of the processor is increased. Any references to findings on this would be helpful.
Lazer
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What's the physical meaning of the imaginary component of impedance?

As you know, impedance is defined as a complex number. Ideal capacitors: $$ \frac {1} {j \omega C} \hspace{0.5 pc} \mathrm{or} \hspace{0.5 pc} \frac {1} {sC} $$ Ideal inductors: $$ j \omega L \hspace{0.5 pc} \mathrm{or} \hspace{0.5 pc} sL $$ I know…
Venemo
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How do computers store sound waves just by sampling the amplitude of a wave and not the frequency?

All of this just doesn’t make sense though. I mean, doesn’t the amplitude represent the loudness and the frequency the pitch? Aren’t they completely independent from each other? Is the book just lacking information or am I just not getting…
RedP
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Is the voltage ever undefined?

I was in a question in Electronics SE, and a lot of people said something that I'm sure is wrong. They said, "The voltage between two points that are not part of the same circuit is undefined". Or in other words, "if I have a circuit that is fully…
Juan Perez
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Does a Mobius resistor have zero inductance? How would you calculate the inductance?

Wikipedia describes a Möbius resistor as follows, and the Patent for this device gives a similar description. A Möbius resistor is an electrical component made up of two conductive surfaces separated by a dielectric material, twisted 180° and…
Truth
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What's the size of the smallest possible pixel size that can be physically detected using an electronic device?

For a given wavelength $\lambda$, is there a limit on the size of the sensor pixel, regardless of the optical equipment attached to the sensor or the nature of the censor?
Michael
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Why does an MRI machine or other EMP generating machine not damage humans, but it will fry computers?

A sufficiently strong electromagnetic pulse can/will destroy smartphones and computers. I know somebody who went into MRI machine and forgot a Visa credit card in his pocket. The card was toast and he had to get a new one. A mobile phone in an MRI…
ShoulO
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Why do you only hear high frequencies when a microphone is near its speaker?

The phenomenon I'm talking about is positive feedback, as known from control engineering: when the microphone is too close to its speaker, it can "hear itself", so the signal will be infinitely amplified. This can be very irritating e.g. during a…
BNJMNDDNN
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Are neurons more energy efficient than transistors?

In terms of order of magnitude, how does a the energy consumption of a typical mammalian neuron (in the brain) compare with the state of the art MOSFET?
user1576720
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Is it viable or possible to make your own transistor?

Just wondering if it is possible/viable to construct your own transistor, not small like todays, but the same scale as the one created at Bell Labs.
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Why does a capacitor act as a frequency filter?

What is it about a capacitor which allows it to filter frequencies? I understand the construction of a high-pass RC filter, and the mathematics behind it, but I'm struggling to find an explanation of the physics behind the phenomenon. In my mind I…
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