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RG_100508411-Visitor
1-Visitor
November 21, 2021
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Re: These units are not compatible

  • November 21, 2021
  • 3 replies
  • 5393 views

Hi, 

I'm trying to input this equation into mathcad, but I keep coming into the problem of incompatible units. Thanks for the help. This is also my first time exploring physics so it may equally be my fault. The equation is in the image attached.

  

 

Best answer by StuartBruff
@RG_10050841 wrote:

Hi, 

I'm trying to input this equation into mathcad, but I keep coming into the problem of incompatible units. Thanks for the help. This is also my first time exploring physics so it may equally be my fault. The equation is in the image attached.

2021 11 21 A.png

 

Mathcad Prime Express 7 worksheet attached.

 

Stuart

 

Edit:  The end of my 3rd paragraph should read "... and it doesn't know you can't add them".

3 replies

S
StuartBruff23-Emerald VAnswer
23-Emerald V
November 21, 2021
@RG_10050841 wrote:

Hi, 

I'm trying to input this equation into mathcad, but I keep coming into the problem of incompatible units. Thanks for the help. This is also my first time exploring physics so it may equally be my fault. The equation is in the image attached.

2021 11 21 A.png

 

Mathcad Prime Express 7 worksheet attached.

 

Stuart

 

Edit:  The end of my 3rd paragraph should read "... and it doesn't know you can't add them".

    R
    RG_100508411-VisitorAuthor
    1-Visitor
    November 21, 2021

    Thank you! I am very fresh to the software and there is a strong chance I'm an idiot. Thank you for your help in my struggles.

     

    R

    S
    StuartBruff23-Emerald V
    23-Emerald V
    November 21, 2021
    @RG_10050841 wrote:

    Thank you! I am very fresh to the software and there is a strong chance I'm an idiot. Thank you for your help in my struggles.

    No worries.  One of the main ideas for this Community is to help people get over the initial learning barriers.  Take comfort from the fact that you are not the first person to have this problem and are very unlikely to be the last.

     

    Sometimes even the experienced can puzzle over some error or unexpected/inconsistent outcomes!   (My bête noire is forgetting that the vectorize operator doesn't apply to the matrix transposition operator 😖)

     

    Stuart

    W
    Werner_E25-Diamond I
    25-Diamond I
    November 21, 2021

    Additionally to what Stuart already explained in detail you may consider using the built-in gravity constant g:

    Werner_E_0-1637501378066.png

    Please also note that to assign a variable (like y) a value, you have to use the assignment or definition operator (":=") and not the comparison equal to (the fat "=") as you did.

      M
      MP_101841353-Newcomer
      3-Newcomer
      January 27, 2022

      Hi my name is Mike Plunkett and I have been using MathCad for at least 20 years. I just got MathCad 7 and love it. Can you tell me how to make US my domain

      unit.  For example, when I open MathCad 7 it goes to SI unit all the time, how can I get it to go to USCI  unit all the time.

       

      Mike Plunkett

      S
      StuartBruff23-Emerald V
      23-Emerald V
      January 27, 2022
      @MP_10184135 wrote:

      Hi my name is Mike Plunkett and I have been using MathCad for at least 20 years. I just got MathCad 7 and love it. Can you tell me how to make US my domain

      unit.  For example, when I open MathCad 7 it goes to SI unit all the time, how can I get it to go to USCI  unit all the time.

       

      Hi Mike,

       

      Try this.  Under the Math tab in the Ribbon, select Units then choose the USCS system in the Unit System: drop down.  Seems to work.

       

      StuartBruff_0-1643297419481.png

       

       

      Stuart

      M
      MP_101841353-Newcomer
      3-Newcomer
      January 27, 2022
      Stuart: I tried just what you said went to the *Math tab,* then the
      *unit System
      then use the pull down menu and hit USCS*

      So for the calculation, I'm working on it stays on USCS, BUT when I open
      another calculation in my file it goes back to SI units??

      Mike Plunkett
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