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Calculate the wavelength of a proton with energy 2.45 eV. what's different between proton and photon formula? can anyone tell me? thank you
Are you sure you are going to calculate the energy of a proton and not a photon? A "proton" is atomic materiale. a "photon" however is a light particle and can for an example be admitted when an electron falls to a lower energy state.
one formula (planck's) is for massless particles (i.e. photons) the other (deBroglie's) is for things with mass... so, for this question, find the velocity, v, of the particle: \[K.E.=\frac{ 1 }{2 }mv ^{2}\] then use the deBroglie equation: \[\lambda=\frac{ h }{ mv }\] wavelength is in meters, velocity in m/s, mass in Kg.