Alternative transcript:

Rest energy (energy "Stored in maas") = E = mc² (this equation only applies to resting mass. • The notation for rest energy is Eo. -27 -31 their into photons. mass Rest Energy (MeV) These two are equivalent (only are changed) energy Even though light is macsless, it has momentum (p=mv) the form of 9381.3) energy Mass increases as kinetic energy increases E=mc²) 939(.6) a nucleus or an electron can change into a particle- antiparticle • One electron volt is defined as the energy transferred when an electron is moved through a potential difference of 1 volt. • Given the rest mass of a particle/antiparticle, its rest energy in Mev Can be calculated using E = mc² Voltage = Energy / Charge (E/e) ⇒ E= ev antiparticle 0.51 (1) is O units Punxi but Due to >E=mc² converted into EM energy gamma ray photons. particle Conservation of energy in annihilation Energy cannot be created nor destroyed. • The energy of the two photons, 2hf particle and antiparticle: 2hf min . Minimum energy Pair Production UUMIY - B + B+ ⇒ 2° 8 В Eg of 0 +1 a Conservation of = 2E. factoring of each photon produced, hf min 1 a particle and corresponding antiparticle and vanishes •In pair production, a photon creates • Pair production only happens if there • It must always produce 9 particle and its comesponding antiparticle because certain quantities is enough energy to produce the masses of the particles. must be conserved. energy, momentum, baryon number, lepton number, charge, strangeness. • Pair production can also be used to produce protons by firing two lot of kinetic energy. Energy is more particles. with converted to in pair production energy Energy cannot be created One photon must produce particles that are produced. → Rest energy of a particle is the amount transformed into energy. Mininum energy ß + +1 (derived from equation E = hf) should equal to min Use of annihilation • PET Scans (Positron emitting tomography) work by putting a positron-emitting isotope into the blood, and detecting the gamma rays produced by the electron-positron annihilation that occurs. 2Eo 2mo Εγ 2mo Ey=hf = 2mo of photob needed с rest energy ( mc²) nor = destroyed. 9 particle - anti particle pain rest of hfmin mas a • The gamma rays are always produced in pairs moving in opposite directions, so they're easily distinguished by Scintillator. (machine to form image> energy protons - the minimum energy being the that would be = 2E.. the rest energy of the m lonly gamal photons have enough energy) 10 total rest the process. energy produced if all of its rest energy of particle type produced in Mev (mc²) particle antiparticle of the a mass was