# Physical Constants

### Acceleration Due to Gravity

$$g = 9.806 65 E+00 \frac{m}{s^2}= 3.217 405 E+01 \frac{ft}{s^2}$$

### Alpha Particle Rest Mass

$$m_{\alpha} = 6.644 656 20(33) E-27 kg = 4.001 506 179 127(62) E+00u$$

### Alpha Particle Rest Mass Equivalent Energy

$$m_{\alpha} c^2 = 3.727 379 109(93) E+03 MeV$$

### Atomic Mass Unit = ($$\frac{10^{-3} \frac{kg}{mol}}{N_A}$$)

u = 1.660 538 782(83) E-27 kg

### Atomic Mass Unit-Electron Volt Relationship

1 uc2 = 9.314 940 28(23) E+02 MeV

### Avogadro Constant (entities per mole)

NA = 6.022 141 79(30) E+23

### Bohr Magneton = $$\frac{e \hbar}{2m_e}$$

$$\mu_B = 9.274 009 15(23) E-24 \frac{J}{T}$$

$$\alpha _o 5.291 772 106 E-11 m$$

### Boltzmann Constant = $$\frac{R}{N_A}$$

$$k = 1.380 650 4(24) E-24 \frac{J}{K} = 8.613 43(15) E-05 \frac{eV}{K}$$

### Characteristic Impedance of Vacuum = $$(\frac{\mu_0}{\epsilon_0})^{\frac{1}{2}}$$

$$Z_0$$ = 3.767 303 134 61 E+02 Ohms

### Classical Electron Radium = $$\alpha^{2}\alpha_0$$

$$r_e$$ = 2.817 940 289 4(58) E-15 meters

### Deuteron Rest Mass

$$m_d$$ = 3.343 583 20(17) E-27 kg = 2.013 553 212 724(78) E+00 u

### Deuteron Rest Mass Equivalent Energy

$$m_d c^2$$ = 1.875 612 793(47) E+03 MeV

### Electron Charge to Mass Ratio

$$\frac{-e}{m_e} = -1.758 820 150(44) E+11 \frac{C}{kg}$$

### Electron Rest Mass

$$m_e = 9.109 382 15(45) E-31 kg = 5.485 799 0943(23) E-04 u$$

### Electron Rest Mass Equivalent Energy

$$m_e c^2 = 5.109 989 10(13) E-01 MeV$$

### Elementary Charge

e = 1.602 176 487(40) E-19 coulomb

$$F = 9.648 533 99(24) E+04 \frac{C}{mole}$$

### Fine-structure constant

$$\alpha$$ = 7.297 352 5376(50) E-03 (dimensionless)

### Gravitational Constant

$$G = 6.674 28(67) E-11 \frac{N \ m^2}{kg^2}$$

### Molar Gas Constant

$$R = 8.314 472(15) E+00 \frac{J}{mole \ kelvin}$$

### Molar Mass Constant

$$M_u = 1 E-3 \frac{kg}{mol}$$

### Neutron Rest Mass

$$m_n = 1.674 927 211(84) E-27 kg = 1.008 664 915 97(43) E+00 u$$

### Neutron Rest Mass Equivalent Energy

$$m_n c^2 = 9.395 653 46(23) E+02 MeV$$

### Permittivity of Free Space (Electric Constant) = $$\frac{1}{\mu_0 c^2}$$

$$\epsilon_0 = 8.854 187 817 E-12 \frac{C^2}{J \ m} = 8.854 187 871 E-12 \frac{F}{m}$$

### Planck Constant

h = 6.626 068 96(33) E-34 Js = 4.135 667 33(10) E-21 MeV second

### Proton mass to electron mass ratio

$$\frac{m_p}{m_e} = 1.836 152 672 47(80) E+03$$

### Proton Rest Mass

$$m_p = 1.672 621 637 E-27 kg = 1.007 276 466 77(10) E+00 u$$

### Proton Rest Mass Equivalent Energy

$$m_p c^2 = 9.382 720 13(23) E+02 MeV$$

### Speed of Light

$$c = 2.997 924 58 E+08 \frac{m}{s}$$

NuclideHalf-lifePhoton Energy
(MeV)
HVL