Page 316 - Biofuels Refining and Performance

Appendix

Relevant Definition
of Energy/Work Units

Btu British thermal unit. Heat energy necessary to raise the temper-
ature of 1 lb of water 1 F.

cal or gcal Calorie or gram calorie. Heat energy required to raise the
temperature of 1 mL of water 1 C (from 15 to 16 C).

12 19
electron volt 1.6 10 erg 1.6 10 J 23.06 kcal/mol. Energy
gained by an electron passing through a potential of 1 V.
foot
pound ft
lb. Work energy needed to raise 1 lb to a height of 1 ft
0.138 kg
m.

force Correct force definition can be obtained from the second law of
Newton stating that the inertia is disturbed by unbalanced force, which
causes acceleration on a body directly proportional to the force (F) and
inversely proportional to the mass of the body F Kmf (F Kmf where
m is mass and f is acceleration). If all are reduced to unity, the unit of
force becomes pound foot per second per second (poundal) or gram cen-
timeter per second per second (dyne).

joule Work energy to raise 1 kg to a height of 10 cm 0.1 kg
m
0.74 ft
lb.

joule (electrical) 0.239 cal. Energy developed when 1 C of electrons
6
(10.364 10 mole) passes through a potential of 1 V.
kcal/einstein Energy of a mole of a photon (einstein) of wavelength (in

) 28589.7
1 kcal/mol.

power Rate of doing work, P W/t.
J/s W or ft
lb/s
or horsepower 550 ft
lb/s or 33,000 ft
lb/min.

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