## Level 2 (without higher mathematics)

**Level 2** requires school mathematics. Suitable for pupils.

## Table of contents

- Speed of light
- Elementary charge
- Vacuum permeability
- Vacuum permittivity
- Planck's constant
- Gravitational constant
- Boltzmann constant
- Electron mass
- Proton mass
- Neutron mass
- Avogadro constant
- Gas constant

## Speed of light

Speed of light tells us how fast light travels in empty space (vacuum).

** Value of the speed of light ** Formula anchor $$ \begin{align} c ~=~ 2.997 \, 92458 \, \frac{\mathrm m}{ \mathrm s} \end{align} $$ ## Elementary charge

The elementary charge is the smallest, freely existing electric charge in our universe.

** Value of the elementary charge ** Formula anchor $$ \begin{align} e ~=~ 1.602 \, 176 \, 643 ~\cdot~ 10^{-19} \, \mathrm{C} \end{align} $$ ## Vacuum permeability

The vacuum permeability appears in equations that deal with magnetic fields.

** Value of the vacuum permeability ** Formula anchor $$ \begin{align} \mu_0 ~\approx~ 1.256 \, 637 \, 062 ~\cdot~ 10^{-6} \, \frac{\mathrm{Vs}}{\mathrm{Am}} \end{align} $$ ## Vacuum permittivity

The vacuum permittivity occurs in equations that deal with electric fields.

** Value of the vacuum permittivity ** Formula anchor $$ \begin{align} \varepsilon_0 ~\approx~ 8.854 \, 187 \, 8128 ~\cdot~ 10^{-12} \, \frac{\mathrm{As}}{\mathrm{Vm}} \end{align} $$ ## Planck's constant

The Planck's constant, is a physical constant that appears in equations whenever the equation describes quantum effects.

** Value of the Planck constant ** Formula anchor $$ \begin{align} h ~=~ 6.626 \, 070 \, 15 ~\cdot~ 10^{-34} \, \mathrm{Js} \end{align} $$ ## Gravitational constant

The gravitational constant occurs in Newton's law of gravity and Einstein field equations, which describe the interaction between masses.

** Value of the gravitational constant ** Formula anchor $$ \begin{align} G ~\approx~ 6.674 \, 30 ~\cdot~ 10^{-11} \, \frac{ \mathrm{m}^3 }{ \mathrm{kg} \, \mathrm{s}^2 } \end{align} $$ ## Boltzmann constant

The Boltzmann constant occurs in equations which describe systems with many particles.

** Value of the Boltzmann constant ** Formula anchor $$ \begin{align} k_{\text B} ~=~ 1.380 \, 649 ~\cdot~ 10^{-23} \, \frac{\mathrm{J}}{\mathrm{K}} \end{align} $$ ## Electron mass

The mass of one electron

** Electron mass value ** Formula anchor $$ \begin{align} \class{brown}{m_{\text e}} ~\approx~ 9.109 \, 383 \, 701 \, 5 ~\cdot~ 10^{-32} \, \mathrm{kg} \end{align} $$ ## Proton mass

Mass of one proton

** Value of the proton mass ** Formula anchor $$ \begin{align} \class{brown}{m_{\text p}} ~\approx~ 1.672 \, 621 \, 923 \, 69 ~\cdot~ 10^{-27} \, \mathrm{kg} \end{align} $$ ## Neutron mass

Mass of one neutron

** Value of the proton mass ** Formula anchor $$ \begin{align} \class{brown}{m_{\text n}} ~\approx~ 1.674 \, 927 \, 498 \, 04 ~\cdot~ 10^{-27} \, \mathrm{kg} \end{align} $$ ## Avogadro constant

The Avogadro constant indicates how many particles are present in *one mole*.

** Value of the Avogadro constant ** Formula anchor $$ \begin{align} N_{\text A} ~=~ 6.022 \, 140 \, 76 \cdot 10^{23} \, \frac{1}{\mathrm{mol}} \end{align} $$ ## Gas constant

The (universal) gas constant occurs in thermodynamics - in the description of gases (e.g. air).

** Value of the gas constant ** Formula anchor $$ \begin{align} R ~=~ 8.314 \, 462 \, 618 \, 153 \, 24 \, \frac{\mathrm{J}}{ \mathrm{K} \, \mathrm{mol} } \end{align} $$