Hi,

I am trying to use SMath to do a calculation using an empirical formula. This formula is used to initially estimate the bending strength of a concrete shaft. For this equation the variable "D" (diameter of the concrete shaft) must be in feet. The answer will be in kip*ft. I have:

D:= 4 ft
M:= 27 * D^3 = 1,728 kip*ft

27 is an empirical constant. Is there a way to ensure that SMath uses "D" in feet for this calculation? Obviously this is a simple equation to check by hand, but I want to use this as part of a more complex calculation sheet. I would like to have confidence that SMath is consistently doing the calculation with "D" in feet.

The alternative case, which I am concerned about is:

D:= 4 ft
M:= 27 * D^3 = 2,985,984 kip*ft
In this scenario the calculation is made using "D" as 48 inches.

Thanks for the help

-Dale

Divide "D" by the desired input unit, multiply everything for the output unit

M:(27*(D/'ft)^3)*'kip*'ft

Edited by user 29 March 2016 00:47:34(UTC)  | Reason: Not specified