Physical Quantities

(SI-, French-, Metric- or MKSA-Units)

 Prefix Symbol Value milli- m 0.001 centi- c 0.01 Kilo- k 1000 Mega- M 1,000,000

 Quantity Symbol Unit Unit’s symbol Relationship Displacement l meter m, km, mm # in, mile # 1 in = 25.4 mm # 1 mile = 1.609 km Mass m kilogram kg, t 1 ton = 1000 kg Time t second s, min, h 1 minute (min) = 60 s 1 hour (h) = 3,600 s * Angular displacement θ rad 1 rad = 180/π  o Area A (l2) m2, cm2, mm2 Volume V (l3) liter cc  (cm3) m3,  L,   cc # gal, in3 l L = 1000 cm3 (cc) # 1 in3 = 16.3871 cc              = 0.01639 L # 1 Gallon (US) = 3.7854 L # 1Gallon (UK) = 4.5461   L Velocity v (l/t) m/s, km/h # mile/h (mph) 1 m/s = 3.6 km/h # 1 mile/h = 1.609 km/h * Angular Velocity ω N rad/s, rpm ω = 2π N/60 Acceleration + a (l/t2) m/s2 (km/h)/s    [car] * Angular Acceleration α rad/s2 Force F (m.a) Newton N, kN 1 N = 1 kg m/s2 Weight w, G Newton N, kN # lb w = m.g = m x 9.81 # 1 lb = 4.44822 N Pressure § p (F/A) Pascal Pa, kPa, MPa # psi 1 Pa = 1 N/m2 1 MPa = 1 N/mm2 # 1 psi = 6894.76 Pa Torque T (F.l) N.m # lb.ft # 1 lb.ft = 1.356 N.m Energy, Work W (F.l) Joule J, kJ #Btu 1 J = 1 N.m 1 J = 1 W.s # 1 Btu = 1.05506 kJ Power P (W/t) Watt horsepower W, kW PS, #bhp 1 Watt = 1 N.m/s            = 1 J/s P = T.ω   [engine] P = F.v    [car] 1 PS = 75 kg.m/s # 1 bhp = 550 lb.ft/s 1 kW = 1.36 PS #1 bhp = 1.0142 PS #1 bhp = 0.7457 kW Density ρ (m/V) kg/m3, kg/L # lb/ft2 # 1 lb/ft3= 16.018   kg/m3 Fuel Consumption kg/h, L/h L/(100 km), km/L # mile/gal       (mpg) [engine] [car]   # x  mile/gal (US) =  x / 2.353  km/L = (235.26/x)  L/100   km # x  mile/gal (UK) = x / 2.825 km/L = (282.48/x)  L/100   km Temperature tc Degree Celsius oC, K (Kelvin), # oF (Fahrenheit) x  Kelvin = x - 273.15  oC # x  oF = (x - 32) 5/9   oC Calorific value kJ/kg # Btu/lb # Btu/lb = 2.324 kJ/kg Standard gravity g 9.80665 m/s2 = 32.1740 ft/s2

§ Other units of pressure:

bar = 0.1 MPa

# Imperial (English) units

* Angular

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