Note 1.J Units of the Systeme Internationale
measure name of unit value conversion to SI units length meter (m) base unit 1 inch = 0.025 4m micrometer (mm) 10-6 m 1 foot = 0.304 8m 10-3 m 1 yard= 0.914 4m 103 m 1 mile= 1,609m millimeter (mm) kilometer (km) mass kilogram (kg) base unit 1 ounce avoirdupois = 28.35g* milligram (mg) 10-6 kg 1 pound = 0.453 6kg gram (g) 10-3 kg 1 stone = 6.350kg 103 kg 1 hundredweight = 50.80kg tonne (t) 1 US ton = 907.2kg 1 ton = 1,016kg time second (s) base unit minute (min) 60s hour (h) 3,600s day (d) 86,400s year (a) 365.25 days area square metre (m2) SI unit 1 square inch = 6.452cm2* square centimetre (cm2) 10-4 m2 1 square foot = 0.092 90m2 hectare (ha) 104 m2 1 square yard = 0.836 1m2 square kilometre (km2) 106 m2 1 acre = 0.404 7ha* 1 square mile = 2.590km2* volume cubic metre (m3) SI unit 1 cubic inch = 16.39cm3* cubic centimetre (cm3) 10-6 m3 1 cubic foot = 0.028 32m3 litre (L) 10-3 m3 1 cubic yard = 0.764 6m3 10-6 m3 1 fluid ounce = 28.41mL* 103 m3 1 British pint = 0.568 3L* millilitre (mL) 1 British gallon = 4.546L* megalitre (ML) 1 bushel = 36.37L* 1 acre foot = 1.233ML* velocity metre per second (m/s) SI unit 1 foot per second = 0.304 kilometre per hour (km/h) 0.277 7m/s 8m/s 1 mile per hour = 0.447 0m/s 1 knot = 0.514 4m/s = 1.852km/h* = 1 minute of latitude on Earth per hour 1 km/h = 0.277 8m/s 1 inch per year = 25.40mm/a energy joule (J), i.e. 1 kg.m2/s3 SI unit 1 calorie# = 4.187J kilojoule (kJ) 103 J 1 kilocalorie# = 4187J megajoule (MJ) 106 J 1 British thermal unit = 1.055kJ* 1kWh = 3.600MJ* power watt (W), i.e. 1 J/s, or 1 SI unit 1 calorie per minute = kg.m2/s3 10-3 W 69.78W* milliwatt (mW) 103 W 1 calorie per second = kilowatt (kW) 106 W 4.187W* megawatt (MW) 1 horsepower = 0.745 7kW* energy watt per square metre (W/m2), SI unit 1 calorie per square density i.e. centimetre day flux 1 kg/s3 10W/m2 = 0.484 6W/m2 milliwatt per square 1 kilocalorie per square centimetre centimetre year = 1.328W/m2 (mW/cm2) 1 langley/min = 697.8W/m2 density kilogram per cubic metre SI unit 1 pound per cubic inch= (kg/m3) 10-3 kg/m3 27.70g/cm3= 27.79t/m3 gram per cubic metre (g/m3) 103 kg/m3 1 pound per cubic foot = gram per cubic centimetre 103 kg/m3 16.02kg/m3 (g/cm3) tonne per cubic metre (t/m3) force newton (N), i.e. 1 kg.m/s2 SI unit 1 dyne = 10-4N kilonewton (kN) 103 N 1 pound force = 4.448N meganewton (MN) 106 N 1 poundal = 9.964kN 1 ton force = 9.964kN pressure pascal (Pa) i.e. 1 kg/m.s2 SI unit 1 millibar = 1 hectopascal = and (N/m2) 100Pa stress 100Pa 1 bar = 100 000Pa 1 pound force per square foot = 47.88Pa 1 pound force per square inch = 6.897 kPa 1 inch mercury = 3.386kPa 1 millimetre mercury = 133.3Pa 1 atmosphere = 101.3kPa temperatu kelvin (K) base unit °C = 5 (°F - 32) / 9 re degree Celsius (°C) K - 273.155 angle radian (rad) SI unit 100 degrees = 1.745rad milliradian (mrad) 10 -3 rad 1 degree of latitude on Earth degree (...°) = 111.1km minute (...') 1/60 degree 1 degree per hour second (...") 1/60 = 4.847 x 10-6rad/s minuite
*Not base SI units but derived from them. # A human being eats about 2500 kilocalories per day, not 2500 calories. This is a common confusion.