Units of Measure
WEIGHTS
1 gram………………………………… 0.03527 ounce
1 ounce………………………………. 28.35 grams
1 kilogram …………………………… 2.2046 pounds
1 pound ……………………………… 0.04536 kilogram
1 metric ton …………………………. 0.98421 English ton
1 English ton …………………..…… 1.016 metric ton
MASS
1 slug ………………………………… 32.2 pounds mass = 14.606 kilograms
1 pound mass ………………………. 453.6 grams
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
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
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
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)
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
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
TROY WEIGHT
24 grains …………………………….. 1 pwt.
20 pwt ……………………………….. 1 ounce
12 ounces …………………………… 1 pound
(Used for weighing gold, silver, and jewels
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
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
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
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
LENGTH
1 centimeter …………………………. 0.3937 inches = 0.0328 feet 1 mil …………………………………. 0.001 inch
1 meter ………………………………. 39.37 inches = 1.0936 yards 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
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
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
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
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
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
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
TEMPERATURE CONVERSION
oC = 5/9 (oF - 32)
oF = 9/5 oC + 32