Warpspeed
Solar Wizard
Right at the centre of the Earth, your weight will be zero there too.
Units moderator. There should be a units moderator assigned.
- Thread starter l00semarble
- Start date
Actually, there is no "high enough" for your weight to become zero from distance to a gravity well...
Weight can become zero in orbit, if you are in freefall towards the gravity well.
Weight is a tricky thing...
We are all in freefall around the sun, orbiting on a heavy rock with its own well of gravity... so... we would need to be out of the solar system to be free from a nearby gravity well, but then we would be in freefall around the galaxy center of mass... so, our weight is relative to the nearest center of mass we are not in freefall of...
Relativity... thanks galelleo!
Because you would have weird conversions for your standard distances/lengths when converting e.g. stud spacing from 16 inch/24 inch on center etc. In metric world, for example, studs are spaced 40 cm or 60 cm on center. All the lumber etc. here takes this into account, and you can find that sheets etc. are often dividable by 60 cm in either direction. A '4 by 6' is just 50 mm x 100 mm, and as someone else mentioned, a true 50 mm x 100mm.
Not when all the lumber is in metric too...
;-)
Did say 'practically' zero (which is correct)- it falls off by the 'inverse square' of the distance and so your weight falls off rapidly (you never 'get to zero'- its like the old 'halve a distance each time'- you never get to your goal- ever) but with it falling by the inverse square of the distance, it doesn't take very long (in astronomical distances) to get to 'practically zero'
The earths diameter is approximately 12000km, so the distance from the center to the surface is about 6000km (roughly speaking)- if you have a person weighing 100kg on the earths surface, put them 6000km up in the sky (not orbiting- they won't stay there that long lol ) but at that point, their weight is down to 25kg (but still their mass is 100kg) and every time you double the distance, their weight drops to a quarter of the previous weight...
Put them 12000km up and their weight is now only 6.25kg, keep going higher and each doubling of the distance takes it down to another quarter of the weight....
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Warpspeed
Solar Wizard
The problem is repairing or renovation an old house that was originally built entirely imperial.
For instance, if the original studs were 18 inches apart, and sheets of building material were three feet wide.
If you go out and buy a new sheet of material its 0.9 metres wide. That works out to just over 35.4 inches wide.
So you come up 0.6 inches short.
Its just enough to be really annoying.
For instance, if the original studs were 18 inches apart, and sheets of building material were three feet wide.
If you go out and buy a new sheet of material its 0.9 metres wide. That works out to just over 35.4 inches wide.
So you come up 0.6 inches short.
Its just enough to be really annoying.
Quite frankly, any house old enough to be all imperial in Australia isn't likely to be made that accurately to begin with...
;-)
One farmhouse I lived in, in NSW, they literally just 'lopped the tops of the trees' about a metre off the ground and laid beams from trunk to trunk... literally nothing under the floors was anywhere near square (lol- there were beams running in any direction just to get from tree trunk to tree trunk...) add in decades of extensions and chopping and changing-everything in it was basically 'custom made' when it was being renovated...
;-)
One farmhouse I lived in, in NSW, they literally just 'lopped the tops of the trees' about a metre off the ground and laid beams from trunk to trunk... literally nothing under the floors was anywhere near square (lol- there were beams running in any direction just to get from tree trunk to tree trunk...) add in decades of extensions and chopping and changing-everything in it was basically 'custom made' when it was being renovated...
Warpspeed
Solar Wizard
A lot of inner suburban houses in Sydney and Melbourne were built during the depression (or even before) and are now almost a hundred years old. A great many still survive on rather small blocks that were originally workers cottages. Many have now been turned into trendy yuppie residences and are very expensive, mainly because of the location close to the city centre.
I know them well (lived in a terrace house in Annandale in Sydney for a while lol)- even back in the 80's they were worth a few bob, and their prices now are ridiculously high...
(especially considering their MANY flaws...)
(especially considering their MANY flaws...)
I just forget that I’m senile
OffGridForGood
Catch, make or grow everything you can.
I Canada our building materials use metric for things we don't export to the USA, concrete blocks, rebar, metal doors and frames to fit the metric block sizes.
We use Imperial units for things we Do export to the USA lumber, plywood, gypsum, polystyrene, steel studs.
Then we get stuck trying to make the two systems work together.
If you draw out a house plan in metric, and don't use the actual sizes of plywood/drywall sheets 1219 x 2438 you are in for a world of problems, and cutting waste.
If you actually put the studs at 400mm or 600mm centres, the plywood and gypsum edges will not land on the stud centres. ie a bad day.
So we "pretend" to be metric with lumber, and use tape measures with BOTH sets of units on them!
Working with older buildings is still a problem, since really old stuff the studs will be close to actual size ie a 2x4 will be close to that size - but will also be rough cut lumber with square corners typically. Later lumber was planned and there was no standardization until about 1970's when all the lumber mills agreed to a standard. I guy I know is manager of a large scale sawmill, he tells me they cut all 2x lumber 1.70" thick to allow 0.1 inch of planning off each face to finish 1.50 exactly after kiln drying.
We use Imperial units for things we Do export to the USA lumber, plywood, gypsum, polystyrene, steel studs.
Then we get stuck trying to make the two systems work together.
If you draw out a house plan in metric, and don't use the actual sizes of plywood/drywall sheets 1219 x 2438 you are in for a world of problems, and cutting waste.
If you actually put the studs at 400mm or 600mm centres, the plywood and gypsum edges will not land on the stud centres. ie a bad day.
So we "pretend" to be metric with lumber, and use tape measures with BOTH sets of units on them!
Working with older buildings is still a problem, since really old stuff the studs will be close to actual size ie a 2x4 will be close to that size - but will also be rough cut lumber with square corners typically. Later lumber was planned and there was no standardization until about 1970's when all the lumber mills agreed to a standard. I guy I know is manager of a large scale sawmill, he tells me they cut all 2x lumber 1.70" thick to allow 0.1 inch of planning off each face to finish 1.50 exactly after kiln drying.
wattmatters
Solar Wizard
To be fair, most don't know how the metric system works either
I'm now using kW·h / 100km.
Don't confuse metric with only using base 10.
The SI/metric unit for angular displacement is the radian. 1 radian is an irrational number.
Not really.
Weight is just another word for "force".
Weight = Mass x acceleration
IOW weight is just the specific case where the acceleration value is due to gravity.
Guilty as charged. Lived in Annadale for 20 years. Small weatherboard cottage, renovated it over the time I owned it and then eight years ago we decided to GTFO of the development monster known as Sydney.
Place I was staying in, well it was pretty run down at the time- infested with cockroaches (all the beds had the legs in ice-cream containers full of water to keep them off the beds- it didn't work lol)- a 1950's ??? vintage town gas HWS- you lit with the old 'long matches', and the temp varied by adjusting the water flow rate- only one tap lol and you had to do it all in the right order- turn water on full, turn gas on and light, adjust water flow to get the right temp- then turning it off always remember to turn the gas off first, and then wait 30 seconds before turning the water off, or the heater could 'blow up' as it turned to steam inside it... (that was literally the only hot water in the house- the kitchen sink and bathroom sink were cold water only- if you wanted hot water to wash the dishes up in, you boiled the kettle on the gas stove...)
And the only toilet was out in the back yard- you walked outside to go to loo- at night in winter in Sydney- not fun... (it still had the flap on the back of it for the 'nightwaste men' to empty the old tin can toilets- but had been fitted with a flush toilet- that had the tank right up on the ceiling with a chain hanging down... flushing it, it could be heard several houses away lol
And the electrical system- OMFG- still had the old 'double adapter' fittings in the hanging ceiling lamps, with extension cord style old cloth covered cable running through hooks down to unswitched 3 pin surface mount sockets...
Soooo many ways for that place to try and kill you...
One of these- not sure which one anymore lol- not that there was much difference between them- the original 'cookie cutter housing'...
And the only toilet was out in the back yard- you walked outside to go to loo- at night in winter in Sydney- not fun... (it still had the flap on the back of it for the 'nightwaste men' to empty the old tin can toilets- but had been fitted with a flush toilet- that had the tank right up on the ceiling with a chain hanging down... flushing it, it could be heard several houses away lol
And the electrical system- OMFG- still had the old 'double adapter' fittings in the hanging ceiling lamps, with extension cord style old cloth covered cable running through hooks down to unswitched 3 pin surface mount sockets...
Soooo many ways for that place to try and kill you...
One of these- not sure which one anymore lol- not that there was much difference between them- the original 'cookie cutter housing'...
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From just watching the 'Site Inspections' channel on YouTube, Australian buildings give me nightmares
Depends- some new buildings (especially the 'stamp em out' cookie cutter suburbs, can be a nightmare, most houses built after the 1960's/70's and onwards aren't too bad, older places are solid (it they have stood up for the last 100 years, they must be reasonably solid- but don't expect anything to be 'made to a plan or standards'- it was literally 'do what you thought would work'- with whatever was to hand... in many cases nothing was even measured, just cut by eye, and match to fit...From just watching the 'Site Inspections' channel on YouTube, Australian buildings give me nightmares
Funnily enough, many Australian standards are higher than those found elsewhere in many other countries...
RV8R
Solar Enthusiast
I Canada our building materials use metric for things we don't export to the USA, concrete blocks, rebar, metal doors and frames to fit the metric block sizes.
We use Imperial units for things we Do export to the USA lumber, plywood, gypsum, polystyrene, steel studs.
Then we get stuck trying to make the two systems work together.
If you draw out a house plan in metric, and don't use the actual sizes of plywood/drywall sheets 1219 x 2438 you are in for a world of problems, and cutting waste.
If you actually put the studs at 400mm or 600mm centres, the plywood and gypsum edges will not land on the stud centres. ie a bad day.
So we "pretend" to be metric with lumber, and use tape measures with BOTH sets of units on them!
Working with older buildings is still a problem, since really old stuff the studs will be close to actual size ie a 2x4 will be close to that size - but will also be rough cut lumber with square corners typically. Later lumber was planned and there was no standardization until about 1970's when all the lumber mills agreed to a standard. I guy I know is manager of a large scale sawmill, he tells me they cut all 2x lumber 1.70" thick to allow 0.1 inch of planning off each face to finish 1.50 exactly after kiln drying.
Cut from the same stuff ,,, You & I
304.8mmYou can read ( feel ) the true Canadian Construction Unit Experience in @OffGridForGood posts.
Imperial ,,, 2x4 ,,, Ya learn the word “Nominal” as opposed to “Normal”
.I was chatting with a Civil Buddy of mine, where they were paving a bridge with a waterproofing under the asphalt. To allow for membrane thickness, the Junior guy setting the approach asked how thick the membrane was so he could allow for it ,,, this was all verbal which is a mistake on its own. So the verbal answer was 50 mils ,,, You guessed it the Junior guy set the approach 50mm low = 2” not 50/1000”
. Never give critical information verbally.I think of that every time I drive over that approach. Usually when I don’t know the story behind brand new bridges & screwed up approaches, I just have to make up my own story.
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OffGridForGood
Catch, make or grow everything you can.
Yeah, it is a struggle at times.
Metric should make construction so much easier - try adding up a long string of dimension in Imperial units (feet, inches, fractions) compared to the same long string all in mm. Yeah, I will go have a coffee and come back in half an hour.
I have seen a ton of wasteful use of material as a consequence, instead of the wall lines being some even value in terms of sheet sizes, they will show even numbers in metric that will result in cutting every sheet of plywood, drywall and foam on an entire building, for absolutely no gain.
Worked on many Government buildings, on a few they decided to have "metric ceiling tiles 500mm x 1500mm" - so where did these come from? - yeah the supplier (in USA) re-ran 2.5'x5' commerical tiles through the cutting room to make custom 500 x 1500 tiles for that 300,000 sqft building, at nearly double the per sqft cost of standard tiles. So how do you get a replacement tile later?
And where will the Tee-bar material come from for a 500x1500 ceiling?
YUP - they just re-ran the normal bar through the slot cutters with the new spacing right beside the original slots, to make it a guess for the installer to know "which of these two slots, a few mm apart are the right ones?
But wait! it gets better!
How will the electrician find 1500mm light fixtures to fit that tee-bar grid?
yup, the lights came to the job 1'x4' rivetted into a prefinished white blank-off sheet cut 500mmx1500mm just to fit the grid.
Yah can't make this stuff up people.
Lucky thing, they stopped doing this insanity after a few of these gov office towers were built, and the facilities managers saw the cost/conseqences.
In 2012, Ontario, in it's infinitesimal wisdom did a even dumber thing with metric conversions, they made the "barrier free" minimum door width 930mm
without checking how doors are actually sold. Doors are multiples of 2" increments. You buy a 36" door, or you buy a 38" door. But 930mm is more than 36" (exactly converted 36" is 914.4mm) so all across Ontario (and no other Province or US State that I know of) we must use 38" wide doors instead of 36" wide to meet the new barrier free accessibility requirements. And yes since 36" is standard commercial size, so we pay a premium.
I am all for making public buildings barrier free, but is Ontario's population 2" wider than everywhere else in N.America??
I saw an out of Province Architect design a school built by an out of Province contractor, install 200 36" wide doors - later to fail occupancy inspections...for 14mm "too narrow" to meet code. Offset hinges to the rescue!
I will say, using both systems daily my whole life, I can freely convert between the two systems in my head, and know all the standard sizes of construction items in both units without thinking about it, making it easy to understand our EU/UK/AU/NZ members just as easily as our US neighbours. Were Canadians, we get along with everyone. ok, we try to. LOL.
{rant over, please return to your regular DIY Solar postings}
Metric should make construction so much easier - try adding up a long string of dimension in Imperial units (feet, inches, fractions) compared to the same long string all in mm. Yeah, I will go have a coffee and come back in half an hour.
I have seen a ton of wasteful use of material as a consequence, instead of the wall lines being some even value in terms of sheet sizes, they will show even numbers in metric that will result in cutting every sheet of plywood, drywall and foam on an entire building, for absolutely no gain.
Worked on many Government buildings, on a few they decided to have "metric ceiling tiles 500mm x 1500mm" - so where did these come from? - yeah the supplier (in USA) re-ran 2.5'x5' commerical tiles through the cutting room to make custom 500 x 1500 tiles for that 300,000 sqft building, at nearly double the per sqft cost of standard tiles. So how do you get a replacement tile later?
And where will the Tee-bar material come from for a 500x1500 ceiling?
YUP - they just re-ran the normal bar through the slot cutters with the new spacing right beside the original slots, to make it a guess for the installer to know "which of these two slots, a few mm apart are the right ones?
But wait! it gets better!
How will the electrician find 1500mm light fixtures to fit that tee-bar grid?
yup, the lights came to the job 1'x4' rivetted into a prefinished white blank-off sheet cut 500mmx1500mm just to fit the grid.
Yah can't make this stuff up people.
Lucky thing, they stopped doing this insanity after a few of these gov office towers were built, and the facilities managers saw the cost/conseqences.
In 2012, Ontario, in it's infinitesimal wisdom did a even dumber thing with metric conversions, they made the "barrier free" minimum door width 930mm
without checking how doors are actually sold. Doors are multiples of 2" increments. You buy a 36" door, or you buy a 38" door. But 930mm is more than 36" (exactly converted 36" is 914.4mm) so all across Ontario (and no other Province or US State that I know of) we must use 38" wide doors instead of 36" wide to meet the new barrier free accessibility requirements. And yes since 36" is standard commercial size, so we pay a premium.
I am all for making public buildings barrier free, but is Ontario's population 2" wider than everywhere else in N.America??
I saw an out of Province Architect design a school built by an out of Province contractor, install 200 36" wide doors - later to fail occupancy inspections...for 14mm "too narrow" to meet code. Offset hinges to the rescue!
I will say, using both systems daily my whole life, I can freely convert between the two systems in my head, and know all the standard sizes of construction items in both units without thinking about it, making it easy to understand our EU/UK/AU/NZ members just as easily as our US neighbours. Were Canadians, we get along with everyone. ok, we try to. LOL.
{rant over, please return to your regular DIY Solar postings}
I know the world is changing and there will all ways be some one smarter with terms of correction ready to jump at what you say and this annoys me when it's not necessary. Lets not forget the old school thought which many started out with. We are here to learn and share, not to ridicule and chase away. Were lucky to have a place like this even though it's not perfect to all opinions.
Sparks-n-Splinters
New Member
It may be annoying...
But.
When you want help, it helps those trying to supply the help if the correct terms are used.
And the correct terms help those trying to learn, where the problem is.
Pedantic capitalization corrections seem pointless...
But they make it easier to solve the issues.
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