Acosmic-ray particle has been observed (indirectly) with an estimated energy of 16 j, or about 1020 ev. suppose this particle was a proton (mc2109 ev). (a) what was the velocity of the proton relative to the earth? warning! most calculators do not carry around enough digits to give not the speed of the particle. express your result in terms of the fractional difference between the velocity of the particle and the velocity of light: an answer other than =c, but this is c (b) the diameter of the milky way is about 10s light years. if a photon and this proton raced across the galaxy by what distance would the photon win the race, as measured by an observer at rest with respect to the galaxy? (c) how long would it take the proton to cross our galaxy, as measured by a clock carried along with the proton?