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Interesting. So do you know where they usually go wrong?
Are they not converting lb to kg before multiplying by 9.81?

I think this may be where we metric countries may be at a slight advantage, almost everyone already knows their 'weight' in kg.
 
For the most part I think that they are unaware that kg is not a unit of weight. This is probably due to the fact that virtually everything at the grocery store has a label that says something like: Net Weight, 5 lb (2.27 kg). The few that know what a Newton is are unable to relate it either to pounds or kilograms.

It also doesn't help that some people teach that pounds can be used to measure both force and mass. In my opinion the concept of a pound mass (lbm) is one of the worst units ever conceived.
 
Here ( "Down Under") in Australia and New Zealand we have to be prepared to work with whatever system is thrown at us and most engineers/tradesmen automatically work with both systems as a matter of course.
People of my age (70 or so) were trained in the imperial system then the country "officially" changed to the metric system, but the change wasn't complete as we still had to deal with American machines and goods, converting everything then became the norm and with the advent of calculators this then became no problem at all, so we live with it.
I find that with things like bore and stroke measurements in model aircraft engines is absurd, the bore and stroke are measured in millimetres and the cubic capacity is expressed in cubic inches! and nobody knows how to deal with it. The best advice I can offer on this one is that if you want to convert between ccs and Cu Inches quickly in your head, use a factor of 6. So divide by 6 for ccs or multiply ccs by six for cubic inches - forget the decimal points, this will get you close enough to understanding the conversion. America is now using metric measurements in the automotive and aerospace industries and many others, - China seems to use whatever measurement it feels like on the day! - so the confusion goes on.
As for reading micrometers, sit down and figure it all out (it's not that difficult) over and over till it is imprinted in your brain, don't sell your DTI, it's only a reference or comparator, it can not be 100% accurate unless it is set at the exact angle to the work and who wants to waste time trying to do that! :)
 
I think that Farhenheit is a much better measurement for temperature than Celsius.

Both Fahrenheit and Celsius are arbitrary:

For Celsius: The freezing point of water = 0 and the boiling point of water = 100.

For Fahrenheit: Freezing point of water = 32 and the boiling point of water = 212.

Here's the difference:

Fahrenheit's scale of 0-100 is easily transferred to the human condition. 0 is just really friggin cold and 100 is really friggin hot.
That compares much better than to Celsius where -10 if really cold and 45 is really hot.

So in normal conversation, Fahrenheit is better because it easily translates into a 0-100% scale from cold to hot for a human's existence.
 
It took a young kid quite some time in primary school to learn,(Was poor Gus in 1950)
Pound,shilling,pence,farthing.
Inch,foot,yard,furlong,mile,league.
Sq ft, sq yard,square mile,acre.
fluid ounce,cu.inches,cu.feet. cu. yard.
Ounce,pound,hundred weight,tons etc.
pound force,foot pound,pound foot.
Did Applied Thermodynamics in Imperial. Was fortunate I joined Ingersoll-Rand,USA and was using Imperial units for 32 years to quote air compressors,gas compressors and water pumps.

Took me some time to get use measuring in mm when machining. Found it convenient to use metric screws.Saved me all the trouble looking for nuts and bolts in BSW BSF BA NC NF etc. Not too many shops stock imperial fasteners. Also had a hard time using/reading metric micrometers.I am quite competent now.
I refuse to use metric dial gage. I am still with Imperial Dial Gages.Been aligning pump couplings with Imperial Dial Gage.

Actually the metric system is simple/easy to use compared to the 1/32 1/16 1/8 1/4 1/2 5/8
3/4 inch. They have no pound shilling pence farthing. No oz lb cwt ton .

After 40 years with Imperial , it was hard to go metric. We were bias.

Getting to like using Centrigrade.

Still very confused.
 

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