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Study Materials

MEASURABLE QUANTITIES         COMMON AND SI UNITS                       
Length in x 25.40 = mm
mil x 10-3 = in
ft x 0.3048 = m
yd x 3 = ft
Angstrom x 10-4 = µm
Angstrom x 0.1 = nm
Area hectare x 104 =m2
acre x 43560 = ft2
Volume ft3  x 1728 = in.3
ft3  x  0.02832 = m3
yd3 x 0.7646 = m3
gal x 3.785 = liter = 10-3m3
ounce (U.S. fluid) x 29.57 = cm3
Mass lb x 0.4536 = kg
U.S. ton x 907.2 = kg
Force [N = (kg) (g = 9.807 m2/s)] kip x 1000 = lbf
bf  x 4.448 = N
U.S. ton x 2000 = lbf
kgf x 9.81 = N
metric ton x 9.81 = kN
dyne x 10-5 = N
Unit Weight γw = 1.00 TCM =g/cm3
γw = 62.4 pcf
γw = 9.81 kN/m3
pcf x 0.1571 = kN/m3
Energy joule (J) = N . m
ft . lbf x 1.356 = J
cal x 4.187 = J
erg = dyne . cm
erg x 10-7 = J
Pressure (Common) atm = 760 mm of Hg
atm x 1.0332 = kgf/cm2
psi x 144 = psf
ksf x 1000 = psf
TSF x 2000 = psf
kgf/cm2 x 2048 = psf
kgf/cm2 x 10 = TSM
TSM x 204.8 = psf
dyne/cm2 x 10-6 = bar
Pressure (Pa = N/m2)

bar = 100 kPa
atm x 101.3 = kPa
psi x 6.895 = kPa
psf x 47.88 = Pa
ksf x 47.88 = kPa
TSF x 95.76 = kPa
kgf/cm2 x 98.07 = kPa; x 2.048 = ksf
TSM x 9.807 = kPa
dyne/cm2 x 0.1 = Pa

Coefficient of Permeability cm/s x 864 = m/day
cm/s x 2835 = ft/day
ft/day x 0.3048 = m/day
Coefficient of Consolidation cm2/s x 8.64 = m2/day
cm2/s x 93.0 = ft2/day
in2/min x 0.929 = m2/day
in2/min x 10  = ft2/day
ft2/day x 0.0929 = m2/day
Power watt = J/s
Temperature oC = (o F - 32)/180