Equations

$$ Flux = Wm^{-2} \text{ OR } Js^{-1}m^{-2} $$

$$ \frac{Fm}{Fn} = 2.512^{n-m} \tag{Eq 2.1} $$

$$ m - n = -2.5 * \log_{10}{\frac{Fm}{Fn}} \tag{Eq 2.2} $$

$$ \frac{F_D}{F_d} = \frac{d^2}{D^2} \tag{Eq 2.5}$$

$$ M - N = -2.5 * \log_{10}\frac{L_M}{L_N} $$

$$ m - M = 5 \log_{10}d - 5 \tag{Eq. 2.8} $$

$$ c = \lambda f \tag{Eq 3.1}$$

Electron Volt $$ 1.602*10^{-19}J $$

Planck’s constant in terms of Joules or Electron Volts $$ h = 6.625*10^{-34} Js $$ $$ h = 4.135*10^{-15} eVs $$

Photon Energy (Planck’s Law) $$ E=hf \tag{Eq 3.2} $$

Photo Enerty relative to wavelength $$ E=\frac{hc}{\lambda} \tag{Eq 3.3}$$

Thermal Energy $$ E_{thermal} = \frac{1}{2}mv^2 = \frac{3}{2}kT \tag{Eq. 3.4}$$

Wien’s Law $$ \lambda_{max}T = constant = 2.8978 * 10^{-3}mK \tag{Eq 3.5} $$

Stefan-Boltzmann Law $$ F = \sigma T^4 Wm^{-2} \tag{Eq 3.6} $$

Stefan-Boltzmann constant $$ \sigma = 5.67*10^{-8} W m^{-2}K^{-4} $$

Star Luminosity $$ L = 4 \Pi R^2 \sigma T^4 $$

Surface Area Of Sphere $$ 4\Pi r^2 $$

Flux of Sun $$ F = \frac{L_o}{4\Pi R_o^2} \tag{p.125, Universe}$$ $$ F = \frac{L}{4\Pi d^2} \tag{Eq. 2.4} $$

Ratio of Fluxes $$ \frac{F_0}{F_1} = \frac{T_0^4}{T_1^4} \tag{p.125} $$

Rydberg Constant $$ R = 1.097*10^{7}m^{-1} \tag{Eq. 5.2} $$

Balmer’s formula (wavelength of spectral lines) $$ \frac{1}{\lambda} = R(\frac{1}{4} - \frac{1}{n^2}) $$

Quantised momentum of electron $$nh = n \frac{h}{2\Pi} = mvr $$

Energy level of orbits: $$ E_n = -R_H (\frac{1}{n^2}) \tag{Eq. 5.1} $$ R is the Rydberg Constant