Experiment 1: Converting Units of Measurement
and Other Calculations
Purpose
This laboratory will give you practice (1) converting between physical units and
(2) calculating averages and average deviations.
Procedure Part I
Express the quantities quoted below in all the units shown in the table. Observe the following
rules in the conversion:
(1) Round off to 3 significant digits.
(2) Express quantities in scientific notation.
(See General Physics Laboratory Information for more information on significant digits and
scientific notation.)
The following is a list of the conversion factors you will need for these exercises. The letters
inside the parentheses are the usual abbreviations for these units.
Units of Length
1 meter (m)
1 foot (ft)
1 mile
Units of Time
1 hour
1 year
= 60 minutes
= 365 days
Units of Volume
1 liter (l)
=
= 100 centimeters (cm) = 10-3 kilometers (km)
= 12 inches (in)
= 30.48 centimeters (cm)
= 5,280 feet (ft)
= 1,609 meters (m)
= 3,600 seconds
= 1/24 day
1000 cubic centimeters (cm3)
Watch your units when converting. Make sure the units cancel as needed. For example,
convert 3.31 feet to meters.
33.1 feet x 30.48 cm x 1 m
= 10.08888 m.  10.1 m = 1.01 x 101 m.
foot
100 cm
Round off to 3 significant digits (since 3.31 has only three significant digits) to 10.1 meters and
express this in scientific notation as 1.01 x 101 m.
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Experiment 1
Do one row of conversions as indicated by your instructor. Show your calculations on another
sheet of paper. Write the result in the table.
LENGTH
Cm
m
km
inches
feet
miles
58.9
8.5
TIME
sec
min
hrs
days
years
5.32 x 104
25.5
SPEED
mi/hr
km/hr
m/sec
ft/sec
65.0
330
VOLUME
cm3
m3
in3
1.72 x 104
1.72 x 104
2
ft3
liters
Experiment 1
Procedure Part II
Given the value of g = 980.2 cm/sec2, calculate the velocity v = 2 gh in cm/sec when h is given
in feet. Show one sample calculation. Remember to write all units in all your calculations.
h (feet)
v (cm/sec)
1.0
5.2
Procedure Part III
Given the value of tan , use the tan-1 function on your calculator to find the angle  in both
degrees and radians:
tan 
 (degrees)
 (radians)
-1.0
0.0
25.2
Procedure Part IV
The following are measurements of physical quantities. Find the average of these quantities and
their deviations.
m (grams)
deviation
444
422
417
439
447
439
Averages
Calculate the average percent deviation and the maximum percent deviation. Show your
calculations.
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