单位制换算表
附表1 单位制换算表
长度 1 m = 3.280 8 ft = 39.37 in
1 ft = 1
2 in = 0.304 8 m
1 in = 2.54 cm
1 mile = 5 280 ft = 1.609 3 m
质量 1 kg = 1 000 g =2.204 6 lb = 6.852 1×10-2 slug
1 lb =0.453 59 kg =3.108 01×10-
2 slug
1 slug =1 lbf·s2/ft =32.174 lb = 14.594 kg
时间 1 h = 3 600 s = 60 min
1 ms = 10-3 s
1μs = 10-6 s
力 1 N =1 kg·m/s2 = 0.102 kgf = 0.224 8 lbf
1 dyn =1 g·cm/s
2 = 10-5 N
1 lbf =4.448×105 dyn = 4.448 N = 0.453 6 kgf
1 kgf = 9.8 N = 2.204 6 lbf = 9.8×105 dyn = 9.8 kg·m/s2
能量 1 J =1 kg·m2/s2 = 0.102 kgf·m = 0.238 9 ×10-3 kcal = 1N·m
1 Btu = 778.16 ft·lbf = 25
2 cal = 1 055.0 J
1 kcal = 4 186 J = 427.
2 kgf·m = 3.09 ft·lbf
1 ft·lbf =1.355 8 J =3.24×10-4 kcal = 0.138 3 kgf·m
1 erg =1 g·cm2/s
2 =10-7 J
1 eV = 1.602×10-19 J
1 kJ = 0.947 8 Btu = 0.238 8 kcal
功率 1 W = 1 kg·m2/s2 = 1 J/s = 0.947 8 Btu/s = 0.238 8 kcal/s
1 kW = 1 000 W = 1 kJ/s = 3 41
2 Btu/h = 859 kcal/h
1 hp = 0.746 kW =
2 545 Btu/h = 550 ft·lbf/s
1 马力= 75 kgf·m/s = 735.5 W =
2 509 Btu/h = 542.
3 ft·lbf/s
压力 1 atm = 760 mmHg = 101 325 N/m2 = 1.033 3 kgf/cm2 = 14.695 9lbf/in2 = 1.033 23at 1 bar =105 N/m2 = 1.019 7 kgf/cm2 = 750.06 mmHg = 14.503 8 lbf/in2
1 kgf/cm
2 = 735.6 mmHg = 9.806 65×104 N/m2 14.22
3 3 lbf/in2
1Pa = 1 N/m2 =10-5 bar =750.06×10-5 mmHg = 10.197×10 -5 mH2O
=1.019 7×10 -5 at = 0.986 92 ×10 -5 atm
1 mmHg =133.3 Pa =1.359 5×10-3 kgf/cm
2 = 0.019 34 lbf/in2 = 1Torr
1 mmH2O = 1 kgf/m
2 = 9.806 65 Pa
续表1（完） 比热容 1 kJ/(kg·K) = 0.238 85 kcal/(kg·K) = 0.238 8 Btu/(lb·)
o R 1 kcal/(kg·K) = 4.186 8 kJ/(kg·K) = 1 Btu/(lb·o )
R 1 Btu/(lb·o ) = 4.186 8 kJ/(kg·K) = 1 kcal/(kg·K)
R 比体积 1 m 3/kg = 16.018 5 ft 3/lb
1 ft 3/lb = 0.06
2 428 m 3/kg
温度
273.15C K t T =?o F 9932459.67F 5C 5K
t t T =+=?o o 51R K 9
=
o 常用物理常数
阿伏加德罗常数 231A 6.02210mol N ?=×
波尔茨曼常数
231.38010J/K k ?=× 普朗克常数 346.62610
J s h ?=×? 摩尔气体常数 8.314510J/(mol K)
1.9858Btu/(lbmol R) 1.9858cal/(mol K)R =?=?=?o
1kg 干空气的气体常数 g,a 287.05J/(kg K)29.23kgf m/(kg K)R =?=?? 1kg 水蒸气的气体常数 2g,H O 461.5J/(kg K)R =?
重力加速度
9.80665m/s g = 1物理大气压 1
atm 760mmHg 101.325kPa ==