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Force of law - Rich Holmes - 07-17-2015

Heh! I was just looking at the newly-signed-by-the-governor California legislation AB 367 (and congratulations, CA, on getting that passed) and noticed this item:

Quote:This bill would change all references in statute to model rocket engines to instead refer to model rocket motors.

Well, I guess that settles that argument, at least in CA...  Big Grin

RE: Force of law - BuiltFromTrash - 07-17-2015

Ha!  I never could figure out the difference between 'motor' and 'engine' in this case. Tongue

RE: Force of law - Greg Young - 07-18-2015

Here is MIT's interpretation:

"“The etymologies of ‘motor’ and ‘engine’ reflect the way language evolves to represent what’s happening in the world,” says MIT literature professor Mary Fuller.

The Oxford English Dictionary defines “motor” as a machine that supplies motive power for a vehicle or other device with moving parts. Similarly, it tells us that an engine is a machine with moving parts that converts power into motion. “We use the words interchangeably now,” says Fuller. “But originally, they meant very different things.”

“Motor” is rooted in the Classical Latin movere, “to move.” It first referred to propulsive force, and later, to the person or device that moved something or caused movement. “As the word came through French into English, it was used in the sense of ‘initiator,’ ” says Fuller. “A person could be the motor of a plot or a political organization.” By the end of the 19th century, the Second Industrial Revolution had dotted the landscape with steel mills and factories, steamships and railways, and a new word was needed for the mechanisms that powered them. Rooted in the concept of motion, “motor” was the logical choice, and by 1899, it had entered the vernacular as the word for Duryea and Olds’ newfangled horseless carriages.

“Engine” is from the Latin ingenium: character, mental powers, talent, intellect, or cleverness. In its journey through French and into English, the word came to mean ingenuity, contrivance, and trick or malice. “In the 15th century, it also referred to a physical device: an instrument of torture, an apparatus for catching game, a net, trap, or decoy,” says Fuller.

In the early 19th century, the meanings of motor and engine had already begun to converge, both referring to a mechanism providing propulsive force. “The first recorded use of ‘engine’ to mean an electrical machine driven by a petroleum motor occurs in 1853,” says Fuller.

Today, the words are virtually synonymous. “Language evolves to take on new tasks,” she explains. “Without thinking about it, we adapt to new meanings and leave the old behind.” We talk about our computer’s dashboard, unaware that in the 1840s, the word referred to the board at the front of a carriage that stopped mud from being splashed on the coachman. Similarly, the term “search engine” harks back to the older meaning of “engine” as a contrivance, suggests Fuller. First used in 1984 to mean “a piece of hardware or software,” the phrase may have been informed by Charles Babbage’s 1822 use of “engine” to mean a calculating machine."

Many in the hobby refer to them as engines, as there are no moving parts like motors are presumed to have. I tend to use them interchangeably! Smile

RE: Force of law - BuiltFromTrash - 07-18-2015

Fascinating! No expression is wrong.

I think that "Rocket Propulsor" fits the bill quite well. Don't think that anybody is going to change though.

RE: Force of law - Rich Holmes - 07-18-2015

Some people insist "motor" and "engine" have specific, different meanings, and for all I know they're right — within a particular field of discourse. Mechanical engineering, maybe, or aerospace. 

But as a physicist I know some words mean one thing in physics and another thing in other contexts. (For instance, to a physicist, if you're standing around for six hours holding a 40 pound rock above your head, you're not doing any work.) Likewise, the mechanical engineering meaning or the aerospace meaning is not required to be the model rocketry meaning. In the context of model rocketry, both "motor" and "engine" are used commonly and interchangeably. Which is "correct"? I prefer to be descriptive rather than prescriptive (in this instance!): both are commonly accepted.

I tend to use "motor" in my speech and writing, but have nothing against people who prefer "engine".

RE: Force of law - rstaff3 - 07-18-2015

I am not even internally consistent on this subject Smile

RE: Force of law - Rocketman - 07-19-2015

It is not the generalized term that is at issue. It is in context of rocketry that the two words have distinct meanings.  A liquid engine typically has moving parts such as pumps, valves, regulators.

A solid motor is typically few to no moving parts, unless it has TVC and that might itself be powered by an engine, or a mechanism. The latest trend is squirting liquid into one side or another inside the motor to slightly adjust the thrust  direction.

A consumer solid motor is an entirely static device.  No moving parts or mechanisms.

So it is in context of rocketry the two terms have specific meanings.

It is more disturbing that one and only one state feels they have to add regulations and rules that do not exist elsewhere.  The current bill, AB 467 restates with clarity a permit is required to launch a model rocket.  Nowhere else is that required.  More disturbing is there is no permit process, form, or tradition that makes obtaining that permit sufficiently frictionless that general consumer products sold in stores are as useable as they are buyable.  It also greatly complicates rockets in schools because administrators say, if a permit is required, there  must be a concern, eh?  It raises unwanted and unjustified concerns and procedures for an activity proven 100% safe in 700,000,000 launchings.


RE: Force of law - DBMcCann - 07-20-2015

Can we forceably annex Cali? (and NYC while we're at it?)

RE: Force of law - Greg Young - 07-21-2015

David, did you say you wanted to annex, or jettison NYC? Wink

RE: Force of law - Rocketman - 07-21-2015

(07-20-2015, 11:30 PM)DBMcCann Wrote: Can we forceably annex Cali? (and NYC while we're at it?)

You can begin with a multi-state campaign to tell Cali to back off like it has been asked by its citizens for decades to crickets.  Maybe they will notice when other states begin to care and mock them for sending business their way.