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what is in smath the correct unit for torque moment (force * lenght)? the si-unit is Nm, but smath show J.
Regard
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You can force any unit you like in the result. Simply put the cursor past the J in your result, there is place to input your units. Input N*m, and... you've got the same, because Newton*meter is Joule erisive: Konrad
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Not possible, sorry. And "J" is not the correct Unit (in SI-System) http://en.wikipedia.org/...national_System_of_Unitshttp://en.wikipedia.org/wiki/TorqueFrom WIKI for Torque: Quote: Units
Torque has dimensions of force times distance. Official SI literature suggests using the unit newton metre (N·m) or the unit joule per radian.[7] The unit newton metre is properly denoted N·m or N m.[8] This avoids ambiguity with mN, millinewtons.
The joule, which is the SI unit for energy or work, is dimensionally equivalent to a newton metre, but it is not used for torque. Energy and torque are entirely different concepts, so the practice of using different unit names for them helps avoid mistakes and misunderstandings.[7] The dimensional equivalence of these units, of course, is not simply a coincidence: A torque of 1 N·m applied through a full revolution will require an energy of exactly 2π joules. Mathematically,
E= \tau \theta\
where E is the energy, τ is magnitude of the torque, and θ is the angle moved (in radians). This equation motivates the alternate unit name joules per radian.[7]
Other non-SI units of torque include "pound-force-feet", "foot-pounds-force", "inch-pounds-force", "ounce-force-inches", and "metre-kilograms-force". For all these units, the word "force" is often left out,[9] for example abbreviating "pound-force-foot" to simply "pound-foot". (In this case, it would be implicit that the "pound" is pound-force and not pound-mass.)
Regard
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Hello, Sorry but I think you did it wrong. It is not 'Nm but 'N*'m. See the example please: Open in SMath CloudRegards, Radovan |
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!" |
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noxx wrote: And "J" is not the correct Unit (in SI-System)
noxx wrote: The joule, which is the SI unit
noxx, I only wanted to explain to you why SMath (or Mathcad) gives you Joules when you multiply Newtons by meters. It doesn't suprise me at all, in fact it is the correct behaviour. Mit freundlichen Grüssen Konrad
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I just checked on my calculator. HP48 when I multiply 1_N by 1_m gives 1_N*m, but when I subtract 1_J out of it, it gives 0_J result. So it doesn't convert 1_N*m automatically to 1_J, but when I convert it manually (left shift-J) it does it without error. Konrad
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Originally Posted by: omorr Hello, Sorry but I think you did it wrong. It is not 'Nm but 'N*'m. See the example please: Open in SMath CloudRegards, Radovan Is there any way that I can set N.mm as default unit instead of J ? I am a structural engineer, working pretty much with Nmm, and I need N.mm everywhere in the calculation smath studio sheet, it is odd to see "J" unit in structural engineering calculation, and I just don't want to change J to N.mm here and there all the times. Thank you very much in advance. (PS:// Smath Studio is the best free tool I have ever had )
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Hello, I think, this way is better: Nm:= N*m (I write this most times to the nonvisible area) F:=100 kNL:=5 mmM:=F*L M=500 NmBest regard Peter Image: Edited by user 12 March 2013 22:34:54(UTC)
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Hello. i'm not able to have NM like you. Why?
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Originally Posted by: raph_rf Hello. i'm not able to have NM like you. Why? - units are case sensitive. Capital M is no unit.
- press N then tab, then *, then m then tab
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I typed it in the way kadpeter's example shows, but I'm still getting Joules as the resulting unit of measure... Image: http://snag.gy/n4ZRf.jpgCan anyone walk me through the steps for achieving the results in N*m? Isn't a major issue, but it would be nice to know how to do this.
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Originally Posted by: SolyomCsaba I typed it in the way kadpeter's example shows, but I'm still getting Joules as the resulting unit of measure...
The portable distribution with Maxima has an integrated interactive handbook, accessible via the blue question mark button in the toolbar. There is a chapter on units and a page on units in results display. Let me know if that does not help, may be the description requires improvement. |
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Originally Posted by: SolyomCsaba I typed it in the way kadpeter's example shows, but I'm still getting Joules as the resulting unit of measure... Because you didn't enter the apostroph. In Kadpeter's example you have to type 'Nm:=N*m The apostroph will disappear and Nm become blue
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@mkraska: Thanks for pointing out that there is a portable version of SMath. Great addition to my toolbox. @brotjob: That solved my problem, and my custom units are working more-or-less as I would like them.
Edit: the "Thank" button returns an error. "An error occured."....
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