I wish to calculate the accuracy and precision of laboratory pipettes,
and use the specific gravity of water. However, the specific gravity
of water changes with temperature and this needs to be included in the
equation. I would like to have box in the spreadsheet for the
temperature. I would then like to relate this value to some
pre-determined constants = eg at 22oC specific gravity = 0.9978, at
23oC specific gravity equals 0.9976 etc. Therefore, the calculation
would need to check what value of temperature is entered,
cross-reference the specific gravity value and then use the value in
the equation.

can anyone help?

A VLOOKUP will give you what you want. With a little algebra, you can
also interpolate the results, if that is necessary.

--
Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
I wish to calculate the accuracy and precision of laboratory pipettes,
and use the specific gravity of water. However, the specific gravity
of water changes with temperature and this needs to be included in the
equation. I would like to have box in the spreadsheet for the
temperature. I would then like to relate this value to some
pre-determined constants = eg at 22oC specific gravity = 0.9978, at
23oC specific gravity equals 0.9976 etc. Therefore, the calculation
would need to check what value of temperature is entered,
cross-reference the specific gravity value and then use the value in
the equation.

can anyone help?

VLOOKUP should do the trick

Define your table of Temps and SGs. I called mine "TempSGtable"

Temp S
22 0.997
23 0.997
24 0.997
25 0.997

The following function will return SG values for Temp values placed in cell A1

VLOOKUP(A1,TempSGtable,2,0

Hope this helps

Kevi

----- Lee Parker wrote: ----

I wish to calculate the accuracy and precision of laboratory pipettes
and use the specific gravity of water. However, the specific gravit
of water changes with temperature and this needs to be included in th
equation. I would like to have box in the spreadsheet for th
temperature. I would then like to relate this value to som
pre-determined constants = eg at 22oC specific gravity = 0.9978, a
23oC specific gravity equals 0.9976 etc. Therefore, the calculatio
would need to check what value of temperature is entered
cross-reference the specific gravity value and then use the value i
the equation

can anyone help

why not just have a list of diffrent temps and another with the
co-responding S.G value, and then the formula, (then plot a graph) -
it's this what is commanly done?

a b c
Temp Sp. Garv. forumal
1 .002 = a*b+2
2 .003
3 .004
4 .003
4 .033

and so on?

Good Luck
Ross

I would suggest a small linking of natural science instead
of dull programming:

Function DensWl(TC As Double) As Double
'Liquid water density[kg.dm-3]
DensWl = 0.99965 + (0.00020438 - 0.000061744 * Sqr(TC))
* TC
End Function

-----Original Message-----
I wish to calculate the accuracy and precision of
laboratory pipettes,
and use the specific gravity of water. However, the
specific gravity
of water changes with temperature and this needs to be
included in the
equation. I would like to have box in the spreadsheet for
the
temperature. I would then like to relate this value to
some
pre-determined constants = eg at 22oC specific gravity =
0.9978, at
23oC specific gravity equals 0.9976 etc. Therefore, the
calculation
would need to check what value of temperature is entered,
cross-reference the specific gravity value and then use
the value in
the equation.

can anyone help?
.

Ummm...sorry, but I'm at a loss as to what you are suggesting...

--
Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
why not just have a list of diffrent temps and another with the
co-responding S.G value, and then the formula, (then plot a graph) -
it's this what is commanly done?

a b c
Temp Sp. Garv. forumal
1 .002 = a*b+2
2 .003
3 .004
4 .003
4 .033

and so on?

Good Luck
Ross