INDEX 



805 



Hearing — continued 



distribution of hearing losses (popula- 

 tion), 315 

 sensitivity of the ear, 314 

 Heat, 7 



atomic, 160 



of elements, 160 

 capacity, gases, 163 



materials, various, 157 



vapors, 163 

 combustion (see also Combustion, heats 



of), 179 

 conduction, across air spaces, 114 



at high temperatures (gases), 115 

 content, ammonia, 162 



steam, 169 

 convection in air, 114 



at high temperature, 115 

 definitions, 7 

 dilution of H2SO4, 186 

 dimensional formulas, 2, 57, 58, 59 

 entropy, 8 



steam, 169 

 flow, 136 



conversion factors of units, 136 



different gradients, 137 

 formation, compounds, 185 



ions, 186 

 index, 730 

 latent, 165 



formula for, 167 



fusion, 165 

 elements, 165 



materials, various, 165 



steam, 175 



vaporization, 166 

 elements, 166 

 liquids, 166 

 formulas, 167 

 loss, effect of pressure, 113 



from incandescent filaments, 116 



from platinum wires, 116 

 mechanical equivalent, 8 

 neutralization, 186 

 Peltier, 383 



radioactive materials, 689, 691 

 specific, 155 



elements, 155 



gases, 163 



liquids, 161 



mercury, 161 



solids, 159 



vapors, 163 



water, 161 

 Thomson, 383 

 units, 7, 8 

 values, fuels, 181 

 Hefner unit, 92 



Height, determination by barometer, 613 

 Helium: 



abundance, early type stars, 628 



nebulae, 629 



sun's atmosphere, 627 



universe, 625 

 atomic numbers, 620 

 atomic weights, 47, 619 

 boiling point, 117 



Helium — continued 

 compressibility, 264 

 high pressure, 267 

 conductivity, thermal, 142 

 density, 269, 291 



critical, 276 

 dielectric constant, 436 

 electric dipole moment, 441 

 electron configuration, 582 

 expansion, thermal, 154 

 heat, latent, 166 

 heat capacity, 163 

 index of refraction, 533 

 ionization, energy for production of ion 



pair, 711 

 isotopes, 655 



Joule-Thomson effect. 278 

 magnetic susceptibility, 462 

 melting point, 117 

 molecular data, 640 

 diameter, 644 

 velocities, 640 

 molecules, number of, 645 

 percent in air, 592 

 physical properties, 189 

 pressure, critical, 276 

 resistivity, thermal, 144 

 Rydberg constant, 48, 51, 54 

 temperature, critical, 276 

 Van der Waal's constant, 261, 262 

 vapor pressure, 360 

 velocity of sound in, 306 

 viscosity, 331 

 volume conversions, 260 

 relative, 261 

 Henry, 17, 20 



Heusler magnetic alloys, 451, 458 

 High-energy particles, 657 

 Horizon, 730 



dip, 729 

 Horsepower, 5 

 Horsepower-hour, 5, 21 

 Human body, electrical resistance of, 375 

 Humidity, 596 

 and density, 597 



relative, and vapor pressure, 602, 604 

 water-vapor pressure, 605 



at sea level, 605 

 wet- and dry-bulb thermometer, 602, 604 

 Hydrocarbons, physical properties (light), 

 293 

 viscosity, 329 

 Hydrogen: 



abundance, 625 



early type stars, 628 

 earth, 625 



interstellar space, 629 

 meteorites, 626 

 nebulae, 629 

 sun, 626, 627 

 universe, 625 

 atomic number, 620 

 atomic weight, 619 

 Bohr atom, 579, 622 

 boiling point, 117 

 charge on one gram, 49 

 combustion constant, 179 



