Name:_______________________________Date:_______________Time:____________
Partner(s):____________________________ Course:__________________
________________________________________________________________________
Measurement of density
1) Introduction to the vernier caliper
Dimensions
of the order of tenths of a millimeter (0.1 mm or 0.01 cm) can be measured
using a
vernier caliper. It consists of a main scale and a
movable vernier scale. The main scale is calibrated
in centimeters with a millimeter least count, and the vernier
scale has 10 divisions that cover 9
divisions on the main scale. The left most mark on the vernier
scale is the zero mark, which is
often unlabeled.
A
measurement is made with the vernier caliper by
closing the jaws on the object to be measured
and then reading the position where the zero line of the vernier
falls on the main scale. The
fractional part of a main scale division is obtained by noting which line on
the vernier coincides
with a line on the main scale. Visit this vernier
web site and learn how to use a vernier caliper.
2) Introduction to the micrometer
Dimensions of the order of hundredths of a millimeter (0.01 mm or 0.001 cm) can
be measured
using the micrometer. It has a movable spindle that is advanced by a rotating
thimble. The
ratchet allows slippage of the screw mechanism when a small and constant force
is exerted on the
jaw. This permits the jaw to be tightened on an object with the same amount of
force each time.
The axial main scale is calibrated in millimeters and the thimble is calibrated
in 0.01 mm.
The micrometer should be checked for a zero error, for
it may not read zero when the jaws are
completely closed. In such cases a zero correction has to be
applied to every reading. The zero
error may be either positive or negative. The zero correction is always made by
subtracting the
zero reading from the final reading.
The
micrometer is read by noting the position of the edge of the thimble on the
main scale which
gives the nearest whole main scale division. The position of
the axial line on the circular thimble
scale gives the fractional part of the main scale. Visit this micrometer
web site and learn how to
use a micrometer.
In
this experiment the mass will be measured using an electronic balance.
A. Rectangular Solids
Purpose: To determine the densities of various rectangular solids by measuring their dimensions and mass.
Apparatus:
Electronic balance, foot ruler, vernier caliper,
micrometer,
rectangular solid metals- Al, Cu, Brass, and Fe; sheet metal, and acrylic
block.
Theory: Density = Mass/Volume, Volume = Length x Width x Height.
Data:
Rectangular Solids
|
Mass |
Length |
Width |
Height |
Al |
- |
- |
- |
- |
Cu |
- |
- |
- |
- |
Fe |
- |
- |
- |
- |
Brass |
- |
- |
- |
- |
Sheet metal |
- |
- |
- |
- |
Acrylic block |
- |
- |
- |
- |
Enter
the above data in Excel spread sheet and calculate the volumes and densities.
Also enter the accepted densities and calculate the %Error. Save your data
table.
Accepted densities (in gm/cm^3):
Aluminum
= 2.70 Copper = 8.90 Iron
= 7.85 Brass = 8.40
Steel = 7.80
Gold =19.30
Lead =11.30 Nickel
= 8.75
Platinum =21.54
Silver =10.5
Zinc =
7.10 water = 1.00
Wood = 0.64 Acrylic
= 1.2
B. Cylinders
Purpose: To determine the densities of various cylinders by measuring their dimensions and mass.
Apparatus:
Metal cylinders: Cu, Fe, Steel, Brass, and Al; wood cylinder, length of Cu
wire, electronic balance, foot ruler, vernier
caliper, and micrometer.
Theory: Density =
Mass/Volume, Volume = (Pi x d^2 x
h)/4.
Data:
Cylinder |
Mass |
Height, h |
Diameter, d |
Al |
- |
- |
- |
Steel |
- |
- |
- |
Cu |
- |
- |
- |
Brass |
- |
- |
- |
Fe |
- |
- |
- |
Wood |
- |
- |
- |
Cu wire |
- |
- |
- |
Enter
the above data in Excel below your earlier Data Table, and calculate the
volumes and densities. Also enter the accepted densities and calculate the
%Error. Print a hard copy of the data tables sheet in
landscape orientation.
D. Density of Water
Purpose: Investigate the density of water.
Apparatus: Graduated cylinder, electronic balance, and water.
Theory:
Density = Mass/Volume
Procedure:
1.
Measure the mass of a graduated cylinder in grams (use the electronic balance),
and record it
on the data table.
2. Fill a small amount of water and measure the mass of graduated cylinder and water.
3. Determine the volume of water by reading the water level in the graduated cylinder.
4. Repeat 1-3, by adding water, 9 more times.
DATA
Mass
of the graduated cylinder = ______________
Mass of cyl
+ water |
Volume of water |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
5. Enter the above data in excel and create a column for the mass of water and calculate it.
6. Plot an XY scatter chart and obtain the density of water from the graph. Print a hard copy of your graph.
7.
Density of water from your graph:______________________
D. Density of a penny
Calculate
the density of a penny by measuring its mass, diameter, and thickness.
Data:
Year of penny________________
Measured mass of penny __________
Measured diameter of penny________
Measured thickness (or height) of penny ________
Calculated volume of penny__________
Calculated density of penny____________
Visit
this penny
composition website and calculate an accepted density for your penny. Also
comment about the metal composition of your penny.
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________