Quantum Physics

PHYSICAL CONSTANTSQuantity Symbol Value SI unitSpeed of light in vacuum c 3.00 10 8 m/sPermittivity of free space 0 8.85 10 12 C 2 /N m 2Coulomb constant, 1/4 0 k e 8.99 10 9 N m 2 /C 2Permeability of free space 0 1.26 10 6 T m/A(4 10 7 exactly)Elementary charge e 1.60 10 19 CPlanck’s constant h 6.63 10 34 J sh/2 1.05 10 34 J sElectron mass m e 9.11 10 31 kg5.49 10 4 uProton mass m p 1.672 65 10 27 kg1.007 276 uNeutron mass m n 1.674 95 10 27 kg1.008 665 uAvogadro’s number N A 6.02 10 23 mol 1Universal gas constant R 8.31 J/mol KBoltzmann’s constant k B 1.38 10 23 J/KStefan-Boltzmann constant 5.67 10 8 W/m 2 K 4Molar volume of ideal gas at STP V 22.4 L/mol2.24 10 2 m 3 /molRydberg constant R H 1.10 10 7 m 1Bohr radius a 0 5.29 10 11 mElectron Compton wavelength h/m e c 2.43 10 12 mGravitational constant G 6.67 10 11 N m 2 /kg 2Standard free-fall acceleration g 9.80 m/s 2Radius of Earth (at equator) R E 6.38 10 6 mMass of Earth M E 5.98 10 24 kgRadius of Moon R M 1.74 10 6 mMass of Moon M M 7.36 10 22 kgThe values presented in this table are those used in computations in the text. Generally, the physical constants areknown to much better precision.