Units of Measure
AVOIRDUPOIS WEIGHT
27-11/32 grains ……………………... 1 dram
16 drams …………………………….. 1 ounce
16 ounces ……………………………. 1 pound
25 pounds ……………………………. 1 quarter
4 quarters ……………………………. 1 cwt.
2,000 pounds ……………………….. 1 short ton
2,240 pounds ……………………….. 1 long ton
CUBIC MEASURE
1 cubic centimeter …………………. 0.061 cubic inch 1 liter ………………………………… 0.906 qt. Dry = 1.0567 qts. Liquid
1 cubic inch …………………………. 16.39 cubic cent 1 quart dry ………………………….. 1.101 liters
1 cubic decimeter ………………….. 0.0353 cubic foot 1 quart liquid ………………………… 0.9463 liter
1 cubic foot …………………………. 28.317 cubic dec. 1 dekaliter …………………………… 2.6417 gallons = 1.135 pecks
1 cubic meter ………………………. 1.308 cubic yards 1 gallon ……………………………… 0.375 dekaliter
1 cubic yard ………………………… 0.7646 cubic meter 1 peck ……………………………….. 0.881 dekaliter
1 stere ……………………………….. 0.2759 cord 1 hekoliter …………………………… 2.8375 bushels
1 cord ………………………………… 3.624 steres 1 bushel ……………………………… 0.3524 hekaliter
FORCE
1 pound force ……………………….. 1 slug x 1 foot sec/sec
1 dyne ……………………………….. 1 gram x 1 centimeter sec/sec
1 newton …………………………….. 1 kilogram x 1 meter sec/sec
1 pound force ……………………….. 4.452 newtons
1 newton ……………………………. 100.000 dynes = 0.224 pounds force
1 gram force ………………………… 980.6 dynes
GEOMETRIC FIGURES
Area of a circle ……………………… D2 x 0.7854 = π r2 (r = radius) Area of a triangle …………………… 1/2 altitude x base
Circumference of a circle ………….. π D or 2π r Volume of a cone ………………….. area of base x 1/3 alititude
Area of a sphere ……………………. π D2 - 4π r2 (D + diameter) Area of a trapezoid …………………. 1/2 (sum of parallel sides) x altitude
IMPERIAL LIQUID MEASURE
1 U.S. gallon ……………………….. 0.883 Imperial gallon
1 U.S. gallon ……………………….. 3.785 liters
1 Imperial gallon ……………………. 1.201 U.S. gallons
1 Imperial gallon ……………………. 4.546 liters
1 liter …………………………………. 0.264 U.S. gallons
1 liter …………………………………. 0.220 Imperial gallon
INTERNATIONAL ELECTRICAL UNITS
1 international ohm …………………. 1.000495 absolute ohms 1 international henry ……………….. 1.000495 absolute henries
1 international volt ………………….. 1.00033 absolute volts 1 international farad ………………… 0.999505 absolute farad
1 international ampere ……………… 0.999835 absolute ampere 1 international watt …………………. 1.000165 absolute watts
1 international coulomb ……………. 0.999835 absolute coulomb 1 international joule ………………… 1.000165 absolute joules
LENGTH
1 centimeter …………………………. 0.3937 inches = 0.0328 feet 1 mil …………………………………. 0.001 inch
1 meter ………………………………. 39.37 inches = 3.28 feet 1 mile ……………………………….. 5280 feet = 1760 yards = 1.609 kilometers
1 kilometer ………………………….. 0.62137 miles = 3280 feet 1 yard ……………………………….. 0.9144 meter
1 inch ………………………………… 2.54 centimeters 1 dekameter ………………………… 1.9884 rods
1 foot ………………………………… 0.3048 meters 1 rod …………………………………. 0.5029 dekameters
LIQUID WEIGHT DRY MEASURE
4 gils …………………………………. 1 pint 2 pints ……………………………….. 1 quart
2 pints ……………………………….. 1 quart 8 quarts ……………………………… 1 peck
4 quarts ……………………………… 1 gallon 4 pecks ……………………………… 1 bushel
31-1/2 gallons ………………………. 1 barrel
LONG MEASURE
12 inches ……………………………. 1 foot
3 feet …………………………………. 1 yard
5-1/2 yards ………………………….. 1 rod
40 rods ………………………………. 1 furlong
8 furlongs ……………………………. 1 statue mile
3 miles ………………………………. 1 league
MARINER'S MEASURE
6 feet …………………………………. 1 fathom
120 fathoms …………………………. 1 cable length
7-1/3 cable lengths …………………. 1 mile
5,280 feet ……………………………. 1 statue mile
6,080.2 feet …………………………. 1 nautical mile
MASS
1 slug ………………………………… 32.2 pounds mass = 14.606 kilograms
1 pound mass ………………………. 453.6 grams
METRIC SYSTEM PREFIXES
Mega ………………………………… 1,000,000 Deci …………………………… 0.10
Kilo ………………………………….. 1,000 Centi ………………………….. 0.01
Hecto ………………………………… 100 Milli ……………………………. 0.001
Deka …………………………………. 10 Micro ………………………….. 0.000001
MISCELLANEOUS CONSTANTS
Loge X …………………………………. 2.30259 log10 X
Electronic charge ……………………. 4.8 x 10-10 e.s.u. = 1.60 x 10-20 e.m.u.
Mass units ……………………………. 1.07 x 10-3 x Mev = 6.71 x 10-2 ergs
Speed of light ………………………… 3 x 108 meters/sec
Speed of sound (in air at sea level)… 1100 ft/sec
π = 3.14159
e = 2.71828
POWER
1 Watt ……………………………….. 1 joule/sec
1 horsepower ……………………….. 550 ft. lb/sec = 716 watts
1 Watt ……………………………….. 3.412 BTU/hr = 0.239 gram calorie/sec
P(watts) ……………………………… R (ohms) x I (amperes)2
P(watts) ……………………………… E (volts)2 / R (ohms)
PRESSURE
1 atmosphere ……………………….. 14.69 ponuds/sq inch = 29.92 in. of Hg
1 atmosphere ……………………….. 76 cm of Hg = 33.9 ft of water
1 in. Hg ………………………………. 0.491 pounds/sq. in
Water Pressure pounds/sq. in ……. head in ft x 0.434
SQUARE MEASURE
144 sq. inches ………………………. 1 sq. ft
9 sq. ft ……………………………….. 1 sq. yard
30-1/4 sq. yards ……………………. 1 sq. rod
40 sq. rods ………………………….. 1 rood
4 roods ………………………………. 1 acre
640 sq. acres ……………………….. 1 sq. mile
SQUARE MEASURE
1 sq. mile ……………………………. 2.59 kilometers 1 sq. cm …………………………….. 0.155 sq. inches
1 circular mil ………………………… 0.7854 sq. mils 1 sq. meter ………………………….. 1.196 sq. yards = 10.784 sq. ft
1 sq. inch ……………………………. 1,000,000 sq. mils 1 sq. kilometer ……………………… 0.386 sq. miles
1 sq. decimeter …………………….. 0.1076 sq. foot 1 sq. inch ……………………………. 6.452 sq. centimeters
1 acre ……………………………….. 60 sq. rod 1 sq. foot …………………………….. 929.03 sq. cm = 0.092903 sq. meters
1 sq. yard ……………………………. 0.8361 sq. meters
TEMPERATURE CONVERSION
oC = 5/9 (oF - 32)
oF = 9/5 oC + 32
TIME ANGLES
1 day …………………………………. 86,400 seconds 1 circle ………………………………. 360 degrees
1 year ………………………………… 8760 hours (approx.) 1 radian ………………………………. 57.3 degrees
1 degree ……………………………… 0.01745 radians
TROY WEIGHT
24 grains …………………………….. 1 pwt.
20 pwt ……………………………….. 1 ounce
12 ounces …………………………… 1 pound
(Used for weighing gold, silver, and jewels
WEIGHTS
1 gram………………………………… 0.03527 ounce
1 ounce………………………………. 28.35 grams
1 kilogram …………………………… 2.2046 pounds
1 pound ……………………………… 0.4536 kilogram
1 metric ton …………………………. 0.98421 English ton
1 English ton …………………..…… 1.016 metric ton
WORK & ENERGY - MECHANICAL
1 erg …………………………………. 1 dyne x 1 dentimeter
1 joule ……………………………….. 1 newton x 1 meter = 105 dynes x 102cm = 107 ergs
1 ft lb ………………………………… 1 pound force x 1 foot = 1.356 joules
WORK & ENERGY - HEAT EQUIVALENT
1 BTU raises 1 pound of water 1oF
1 gram calorie raises 1 gram of water 1oC
1 BTU = 252 gram calories = 778 ft lb = 1055 joules
1 gram calorie = 0.003964 BTU  = 4.184 joules
1 horsepower hour = 2544 BTU's
WORK & ENERGY - ELECTRICAL EQUIVALENT
1 joule ……………………………….. 1 watt x 1 second = 1 amp (DC) x 1 volt (DC) x 1 second
W (joules) …………………………… 1/2 L (henries) x 1 (amperes)2
W (joules) …………………………… 1/2 C (farads) x E (volts)2
1 kilowatt hour ……………………… 3,600,000 joules