Quantum Physics Energy Unit Electron Volt Full HD video

Quantum Physics Energy Unit Electron Volt. Hello! In this video I will tell you about electron Volt. Energy unit used in quantum physics and high energy physics. In the classic physics energy unit is Joule. Which is kg * m^2 / s^2. At first you might be confused why there are different energy units in classic physics than in quantum physics? And how to convert from Joule to eV, and from eV to Joule? I will tell you how. In classic physics equation for power is: P=I*U, in units W=A*V Power is also energy divided by time: P=E/t in units W=J/s If we reverse this equation we have: E=P*t in units J=W*s If we use this equation in previous equation, and multiply both sides of equation by time: P*t = I*t * U E=I*t * U in units J=A*s * V But equation for charge is: Q=I*t in units C=A*s so we can substitute again: E=Q*U in units J=C*V Robert Millikan, in his famous oil drop experiment, for which he was awarded Nobel Price, found out that charge is quantized, and only integer multiplies of e, elementary charge, are allowed. Don't confuse it with Euler's Number e. e=1.602176565*10^-19 C In other words Q/e is quantity of electrons. And finally we have: 1.602176565*10^-19 J = 1.602176565*10^-19 C * 1 V 1 eV = 1.602176565*10^-19 J To convert from Joule to eV, divide it by e, and vice versa. Commonly are also used: 1 keV = 1000 eV 1 MeV = 10^6 eV 1 GeV = 10^9 eV In high energy physics there are also used TeV, PeV, and similar. Thank you for watching.