Ohaus Voyager Balances - Manual (Page 287)

46
Balance modes
Q = Density of the solid
A = Weight of the solid in air
B = Weight of the solid in the auxiliary liquid
Q
0
= Density of the auxiliary liquid at a given temperature (this value depends on the temperature). The density table
for water is included in Voyager balances.
P = Buoyancy of the solid in the auxiliary liquid (corresponds to A -B).
In the event that a different liquid is to be used, provisions are made to enter the density of the desired liquid and enter
its name into a library. The following procedure uses water.
6.9.2 Solid density determinations for items more dense than water
The density Q is the quotient of the mass m and the volume V.
Q = m
V
Density determinations are performed by using Archimedes’ principle. This principle states that every solid body
immersed in a fluid loses weight by an amount equal to that of the fluid it displaces. The density table for water is
included in the Voyager balance software.
The density of a solid is determined with the aid of a liquid whose density, Qo, is known (water is used as an
auxiliary liquid). The solid is weighed in air (A) and then in the auxiliary liquid (B). The density Q can be calculated
from the two weighings as follows:
Q =
A
A -B
•Q
0
Thebalance allows direct determination of the buoyancy P (P =A - B ) and consequently the above formula can be
simplified:
Q =
A
P
•Q
0
From main menu
Enter CHANGE MODE. Select DENSITY, display advances to LIBRARY NAME.
MAIN MENU
CHANGE MODE
Enter
DENSITY SETUP
LIBRARY NAME
Library name
Enter a library name, up to 8 characters and press Enter button. Display
advances to DENSITY SETUP with SOLID DENSITY highlighted. If a previous
name was entered and selected, the balance uses the parameters which
were previously set.
DENSITY SETUP
Enter
LIBRARY NAME D2
SOLID DENSITY <-SELECTED
LIQUID DENSITY
AUTO SAMPLE OFF
AUTO PRINT OFF
RUN
After you select SOLID DENSITY, display advances to AUX LIQ & MODE with
H2O highlighted.