How to define a mechanical and non-mechanical device ?

jpanhalt

Joined Jan 18, 2008
8,097
Won't even a solid state relay effectively mechanically disconnect a wire?
My understanding of "mechanical" is apparently different than yours. For example, I do not consider a logic-level mosfet switch driven by an MCU or other logic device as mechanical. To extend that logic, then all logic circuits, even your LCD monitor are mechanical.
 

Thread Starter

Papabravo

Joined Feb 24, 2006
12,511
My understanding of "mechanical" is apparently different than yours. For example, I do not consider a logic-level mosfet switch driven by an MCU or other logic device as mechanical. To extend that logic, then all logic circuits, even your LCD monitor are mechanical.
Opening or blocking a channel is just about as mechanical as you can get. Not being able to see it does not make it inherently non-mechanical.
 

crutschow

Joined Mar 14, 2008
23,516
Opening or blocking a channel is just about as mechanical as you can get. Not being able to see it does not make it inherently non-mechanical.
My definition of "mechanical" does not include solid-state devices, nor do I think of a computer logic operation as mechanical.
So you do?

To me a mechanical operation involves some sort of movement of a physical macro part or device, not the movement (or not) of subatomic electrons or holes. ;)
 

jpanhalt

Joined Jan 18, 2008
8,097
@Papabravo
I disagree. But, if you want to consider transistors as mechanical switches, that's OK with me. Let's ask the TS whether he/she considers transistors mechanical switches. Does anyone else here consider diodes, transistors, resistors, and so forth "mechanical devices?
 

jpanhalt

Joined Jan 18, 2008
8,097
@moderators
I think it is clear what the TS intended and this discussion is non-contributory. If @Papabravo wants to continue with one of the definitions in O.E.D. for a mechanical device (e.g., directing any "force") as applied to electronics, perhaps it deserves its own thread. Or, maybe just an asterisk.

Edit: I think thyristor/triac or SSR (which often include a thyristor or equivalent) answer the TS's question. NB: Some SSR's offer optical isolation too in an "off the shelf," one-chip solution. Moreover, since this is in Digital Circuit Design, those solutions will work with logic voltages for control.
 
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nsaspook

Joined Aug 27, 2009
6,498
Take your pick.

Technical Mechanics is force on a body. The size of the body can be infinitesimal (The simplest mechanical system is the particle) as in Quantum mechanics. This means in physics terms solid-state devices are mechanical as charges move inside them because of force at junctions and other paths in response to potentials. They are physically built just like parts of an engine for specific jobs.

In colloquial Mechanics terms solid-state devices are not mechanical systems.
 

eetech00

Joined Jun 8, 2013
1,723
@Papabravo
Does anyone else here consider diodes, transistors, resistors, and so forth "mechanical devices?
No...diodes, transistors are electronic devices. Mechanical devices exert force between physical parts that cause, or prevent, movement. If you mix an electronic device with a mechanical device, then the device becomes an electro-mechanical device.

eT
 

jpanhalt

Joined Jan 18, 2008
8,097
Take your pick.

Technical Mechanics is force on a body. The size of the body can be infinitesimal (The simplest mechanical system is the particle) as in Quantum mechanics. This means in physics terms solid-state devices are mechanical as charges move inside them because of force at junctions and other paths in response to potentials. They are physically built just like parts of an engine for specific jobs.

In colloquial Mechanics terms solid-state devices are not mechanical systems.
I agree, but in the context of the original question that led to this pedantic exercise, the TS posted,"...without mechanically disconnecting wire/conductor?" It was clear to me what was meant, and it wasn't quantum mechanics. The Oxford English Dictionary (OED) is often used as the final arbitrator of word meaning. One major exception is in the practice of law. These links show a difference between "mechanically" used in the above context and the noun "mechanics" used as the singular. NB, Apparently OED is not easily accessed online. "Lexico.com" appears to be its main interface. I have abridged the following quotes from Lexico links by removing examples and other links for brevity.


"Mechanically"
https://www.lexico.com/en/definition/mechanically
ADVERB
1 By means of a machine or machinery.
1.1 In a way that relates to machines or machinery.
2 Without thought or spontaneity; automatically.

"Mechanics"
https://www.lexico.com/en/definition/mechanics
1 (treated as singular) The branch of applied mathematics dealing with motion and forces producing motion.
1.1 The practical study of machinery.
2 The machinery or working parts of something.
2.1 The way in which something is done or operated.
‘the mechanics of cello playing’


The distinction between "mechanics" used as a singular noun and "mechanically" used as an adverb seems clear.
 
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