Modern Physics Important Concepts for AP TestSpecial RelativityLaws of Physics are same in all inertial reference framesSpeed of light is the same regardless of velocity of observer or source of lightFollowed results of Michelson-Morley Experiment – null result, ether does not exist and velocity of light independent of velocity of earthAbsolute length and absolute time intervals are meaningless. Simultaneity of two events is not an absolute concept but depends on the motion of the observer.Moving clocks run more slowly. (time dilation)Proper length is the longest length. (length contraction)Energy and Relativistic Momentum(equations which may be used in problem section)Rest Energy (particle at rest still has energy associated with its mass)Erest= mc2Energy of photons (massless)E = pcTotal Energy E = K + mc2Pair Production and annihilationProcess in which a photon creates matter. An electron and positron (positively charged particle with mass of an electron) areproduced and the photon disappears.Energy, momentum, and charge must be conserved in this process.