Conversions des unités du SI

Facteurs des unités de convertion


Accélération
1 m/s2 = 100 cm/ s2 = 3.281 ft/ s2
1 cm/ s2 = 0.01 m/ s2 = 0.03281 ft/ s2
1 ft/ s2 = 0.3048 m/ s2= 30.48 cm/s2
1 mi/h .s = 1.467 ft/ s2


Angle
1 rad = 57.30° = 180°/π
1° = 0.01745 rad = π/180 rad
1 revolution = 360° = 2π rad
1 rev/mm (rpm) = 0.1047 rad/s


Aire
1cm2 = 0.155 in.2
1 m2 = 104 cm2 = 10.76 ft2
1 in.2 = 6.452 cm2
1 ft2 = 144 in.2 = 0.0929 m2


Énergie
1 J = 1O7ergs = 0.239 cal
1 cal = 4.186 J (based on 5°calorie)
1 ft.lb = 1.356 J
1 Btu = 1055 J = 252 cal = 778 ft.lb
1 eV = 1.602X 10-19 J
1 kWh = 3.600 x j


Force
1 N = 105 dyn = 0.2248 lb
1 lb = 4.448 N = 4.448 x 105 dyn


Longueur
1 m = 100 cm = l000 mm = 106 µm = 109nm
1 km = 1000 m = 0.6214 mi
1 m = 3.281 ft = 39.37 in.
1 cm = 0.3937 in.
1 in. = 2.540cm
1 ft = 30.48 cm
1 yd = 91.44cm
1 mi = 5280 ft = 1.609 km
1 Å = 10-10 m 10-8 cm = 10-1 nm
1 nautical mile = 6080 ft
1 light year = 9.461 X 1015 m


Masse
1 kg = 103 g = 0.0685 slug
1 g = 6.85 x 10-5 slug
1 slug = 14.59 kg
1 u = 1.661 X 10-27kg
1 kg has a weight of 2.205 lb when g = 9.80 m/ s2


Mass—Energy Equivalence
1 kg <=> 8.988 X 1016 J
1 u <=> 931.5 MeV
1 eV <=> 1.074 x 10-9 u


Puissance
1 W = 1 J/s
1 hp = 746 W = 550 ft• lb/s
1 Btu/h = 0.293 W


Pression
1 Pa = 1 N/m2 = 1.450 X 10-4 lb/in.2 = 0.209 lb/ft2
1 bar = 105 Pa
1 lb/in.2 = 6895 Pa
1 lb/ft2 = 47.88 Pa
1 atm = 1.013 X 105 Pa = 1.013 bar
1 atm = 14.7 lb/in.2 = 2117 lb/ft2
1 mm Hg = 1 torr = 133.3 Pa


Vitesse
1 m/s = 3.281 ft/s
1 ft/s 0.3048 m/s
1 mi/min = 60 mi/h = 88 ft/s
1 km/h = 0.2778 m/s = 0.62 14 mi/h
1 mi/h = 1.466 ft/s = 0.4470 m/s = 1.609km/h
106 pin = l09 nm


Temps
1 mm = 60 s
1 h = 3600 s
1 j = 86,400 s
1 a = 365.24 d = 3.156 x 107 s

Volume
1 litre = 1000 cm3 = 10-3 m3 = 0.03531 ft3 = 61.02 in.3
1 ft3 = 0.02832 m3 = 28.32 litres = 7.477 gallons
1 gallon = 3.788 litres


Remonter