Formatting MPa to the power of (1/3) in Mathcad 15

[Anders]

Hi!

I have created a workset that requires a vairable to be raised to the power of 1/3 (one third). The variable already has the unit MPa, but the unit of the result is a bit messy as seen below. Can i change that back to MPa by any chance? Screenshot below.

I am using Mathcad 15.0 (M050 [MC15_M050_20171129])

Thanks in advance.

[ChrisKaswer · Accepted solution]

You cannot apply units in a relation that does not provide properly balanced units as a result - just like with your situation. If your value for "q" must end-up as units of MPa, because "a" is in this unit, then you can do the following:

You'll need to make sure you always define "a" in MPa as well.

[Anders]

Allright, thanks a lot!

It is not excactly pretty, but it does the job.

[ChrisKaswer]

Agreed, but that's a fundamental issue with using software that deals with units as well as Mathcad - you can't end-up with a "MPa" raised to the 1/3 power, and that's what we're really asking Mathcad to do in your original equation. If there was an additional part of your relation that raised the entire result to the 3rd power, you'd be all set. I've used this approach hundreds of times in the past as it's the only way to deal with these kinds of relationships.

Good Luck

[Fred_Kohlhepp]

Note:  a does not have to be MPa, any stress or pressure unit will do, so long as the definition (in MPa) is valid.

[ValeryOchkov]

You work with an empirical formula!