# Thread: Why 68 Deg. for inspection

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Originally Posted by tomato coupe
Nothing wrong with that, but what happens when you want to measure long distances? kilo-inches? mega-inches?
Miles. Miles have a definite relation to yards, feet, and inches.

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Originally Posted by tomato coupe
Well, then it should be pretty simple to calculate the kinetic energy (E = 1/2 * m * v * v) of a 1 slug object moving at 1 foot per second, in any commonly-used unit of energy.
Yep. Do you know anything about dimensional analysis?

Mass =force/acceleration, so the dimensions of mass are pound.second squared/foot, and E is 0.5 pound.foot.

Pretty easy to convert that to whatever unit of energy you like.

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Originally Posted by cameron
Yep. Do you know anything about dimensional analysis?

Mass =force/acceleration, so the dimensions of mass are pound.second squared/foot, and E is 0.5 pound.foot.
Do you routinely give the mass of common objects in units of (pound) * (second) * (second) / (foot)?

Pretty easy to convert that to whatever unit of energy you like.
Great. Show me how easy it is to convert pound-feet to any common imperial unit of energy.

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Originally Posted by Willy
Back to the original question, much as I like the metric vs. imperial debates or what type of oil should I use in my scooter.

20 °C—A Short History of the Standard
Reference Temperature for Industrial
Dimensional Measurements
I didn't have anything better to do the other night so I read the link you provided. I found some of it very interesting and other parts, well, not so much. But I did learn a lot.

As far as your scooter oil question, isn't it obvious that you should use metric scooter oil

Steve

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Originally Posted by tomato coupe

Great. Show me how easy it is to convert pound-feet to any common imperial unit of energy.
Sure. One Joule is .737 pound-feet. One Joule per second equals one Watt. One Watt equals 3.41 BTU's per hour.

It pays to know your history.

Now, a few years ago I converted all my energy usage into a common basis (joules) to calculate the lowest possible heating bills in February.... e.g BTU's/CF of NatGas vs Elec all expressed in Joules/hr rate of consumption.... NatGas won by the slimmest of margins only because my insulation is so horrible.
Last edited by nickel-city-fab; 07-11-2019 at 10:18 PM.

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The question is.
Why not 68 Deg.?

The people that wrote the standard may have simply liked that temperature (-:

"Hey Fred what temp should we specify?"
"I find 75 to warm and 60 to cold so lets make it 68 Deg."
"That works for me Fred, let it be so"

I suspect that the group that specified the OD of numbered screws worked in the same fashion.

"Hey Fred how do we write the standards for your non-fractional screw standard?"
"How about the major diameter = the screw number X .013" + .06", this should keep people confused for decades"
"I like it Fred so lets run with it"

History was made with bourbon I suspect (-:

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Originally Posted by nickel-city-fab
Sure. One Joule is .737 pound-feet. One Joule per second equals one Watt. One Watt equals 3.41 BTU's per hour.

It pays to know your history.

Now, a few years ago I converted all my energy usage into a common basis (joules) to calculate the lowest possible heating bills in February.... e.g BTU's/CF of NatGas vs Elec all expressed in Joules/hr rate of consumption.... NatGas won by the slimmest of margins only because my insulation is so horrible.
You've just nicely illustrated why the metric system is often easier than the imperial system.

Imperial:
In order to calculate the kinetic energy of a 1 slug mass with a velocity of 1 foot per second, you need to do two conversions. First, you have to convert slugs to (pound) * (second) * (second) / (foot), and then you have to convert the result from (pound) * (feet) to BTU.

Metric:
Calculating the kinetic energy of a 1 kg mass with a velocity of 1 m/s is trivial. The energy is 0.5 J

Edit: Oops, forgot the 1/2 factor
Last edited by tomato coupe; 07-11-2019 at 11:23 PM.

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Tomato...

Your own "argument" here seems to be to attack various statements, and then at the end, agree with it.

People make much of the base ten nature of "metric" or"SI", claiming it is "so logical" and obviously correct due to the decimal units.

My point is, first, that the ONLY reason "SI" is "more correct" or logical, is that it happens to be deliberately made to BE easy, with easy relations between units.

BUT, there is really nothing special about "ten" that affects the way "SI" works.... The same sort of logical relations could be set up using a base thirty system, or base twelve, etc. The super specialness of ten just comes from our fingers, and not some logical argument from the nature of the universe, as many seem to be claiming.

Essentially, what is "blamed on" the base ten nature, is really nothing much to do with it, the "magic" is in the relation between units, which is not dependent on base ten in any way other than being more familiar due to "traditions" that people in western society (at least) tend to share. Folks are looking in the wrong place.
Last edited by J Tiers; 07-12-2019 at 01:08 AM.

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Originally Posted by J Tiers
Tomato...

Your own "argument" here seems to be to attack various statements, and then at the end, agree with it.

People make much of the base ten nature of "metric" or"SI", claiming it is "so logical" and obviously correct due to the decimal units.

My point is, first, that the ONLY reason "SI" is "more correct" or logical, is that it happens to be deliberately made to BE easy, with easy relations between units.

BUT, there is really nothing special about "ten" that affects the way "SI" works.... The same sort of logical relations could be set up using a base thirty system, or base twelve, etc. The super specialness of ten just comes from our fingers, and not some logical argument from the nature of the universe, as many seem to be claiming.

Essentially, what is "blamed on" the base ten nature, is really nothing much to do with it, the "magic" is in the relation between units, which is not dependent on base ten in any way other than being more familiar due to "traditions" that people in western society (at least) tend to share. Folks are looking in the wrong place.
I have not attacked various statements. I made one simple statement

Originally Posted by tomato coupe
A measuring system based on 10 is special because our numbering system is based on 10.

Originally Posted by J Tiers
There is absolutely no "logic" to a measuring system just because it is based on the number 10

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Originally Posted by tomato coupe
Nothing wrong with that, but what happens when you want to measure long distances? kilo-inches? mega-inches?
That is where the "fortnight" comes in. The distance that a three legged dog can travel in 1 fortnight will be the standard for long distances. For shorter distances we use a cat.

If that doesn't work then why not use the deca-inch (100 inches?) instead of the yard and what ever 10,000 inches would be instead of the mile. Then we will convert the standard day to 10 hours divided by 100 minutes each. 10 month each year with 36 days each, there will have to be some kind of leap year adjustment for the 1/2 days or change the orbit of the planet to a 360 day cycle. Of course what happens when part of the world refuses to change over to the new system.

It would just be much simpler for those that wish to continue to use the Imperial system to do so and those that want everyone to only use the metric system to bugger off.

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