Skip to main content
Best answer by Werner_E

The dimension of stiffness is force per length or mass per time^2.

 

So you would have to change the unit for "k" to something like "N/m" or "kg/s^2" for the solve block to work.

 

But using the initial conditions you provide, the solution x(t) trivially would be constant zero.
I guess that you would have to change one of x.0 or x'.0 from zero to a non-zero value.

Here's an example:

Werner_E_0-1586867726547.png

BTW, you may already have noticed - the diagram components you are trying to use are not unit aware

5 replies

L
LucMeekes23-Emerald IV
23-Emerald IV
April 14, 2020

The units of

M * z''

C * z'

k * z

Must be the same. If the units of C and M are OK,  then that of k is wrong. Or the equation is wrong.

The unit of z is m, that of z' is m/s and that of z'' is m/s^2.

 

Success!

Luc.

 

S
SPRstructur15-MoonstoneAuthor
15-Moonstone
April 14, 2020

 

could you correct for me in attachment above?

Thank u

W
Werner_E25-Diamond IAnswer
25-Diamond I
April 14, 2020

The dimension of stiffness is force per length or mass per time^2.

 

So you would have to change the unit for "k" to something like "N/m" or "kg/s^2" for the solve block to work.

 

But using the initial conditions you provide, the solution x(t) trivially would be constant zero.
I guess that you would have to change one of x.0 or x'.0 from zero to a non-zero value.

Here's an example:

Werner_E_0-1586867726547.png

BTW, you may already have noticed - the diagram components you are trying to use are not unit aware

    Terms & ConditionsAccessibility statement