Table of Consistent Units - stress analysis

This is an excellent rationale for using a calculation tool like Mathcad or SMath Studio. I can imagine the millions of hours lost every year tracking down a unit error in some calculation.

BTW, isn't "ton" an English unit; should that be a "tonne"?

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1 tonne = 1000 kg, and not 1e6kg as stated in your conversions

For stress analysis, IPS (inches, pounds-force, seconds) is popular in the US (probably the most popular). Also, stress analysts typically work with base units of length-force-time (not length-mass-time). You can use either, but the "base" should not consist of multiple units.

Brian

Sorry, as said by corus, the worksheet attached to my first post has a mistake: 1 tonne = 1.0e+3 kg, not 1.0e+6 kg.
I've attached a corrected version of the worksheet (link below)

As for the other comments:

- it's true that the table is biased towards the metric system. It is because I don't have much contact with the Imperial system, so any one who think it's appropriate, feel free to enrich the table;

- it was good to mention that, for stress analysis, it is often more convenient to define a set of units based on length-force-time (in a static loading case, for example). I totally agree with that, and that is why the set mm-N-s is in the top of the list. But "base quantities" is a standand "notation" in physics. For dimensional analysis, it was conventioned that those seven quantities are the base quantities - they are independent from each other, and all units can be described as a relation of base units.

Anyway, even if you need a set based on units for length-force-time, it is still easy to find the right line in the table, and them find the correspondent units for time, stress, velocity, etc

Can you add the FFF system?

The length unit is the furlong, the mass unit is the mass of a firkin of water, and the time unit is the fortnight.

Alternatively, there's the “Furlong / Fortnight / Farad / Faraday” system, whose consistent unit of mass is the faraday² fortnight²/(farad·furlong²)

am pretty sure 1000 kg is 1 tonne, not 1 ton.....

The Wikipedia ton page covers the various meanings of "ton" and "tonne" pretty well:


except that it calls it a unit of weight, whereas the tonne (in engineering usage)is a unit of mass.

Doug Jenkins
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