What is the energy of each of the two photons produced in a proton-antiproton annihilation? use the following joules-to-electron-volts conversion 1ev = 1.602 × 10-19 j. the rest mass of a proton is 1.67 × 10 − 27 1.67 × 10 − 27 kg.

Two pans of a balance are 24.1 cm apart. the fulcrum of the balance has been shifted 1.33 cm away from the center by a dishonest shopkeeper. by what percentage is the true weight of the goods being marked up by the shopkeeper? assume the balance has negligible mass. answer in units of %.