How much total kinetic energy will an electron-positron pair have if produced by a 2.60 mev photon? use the following joules-to-electron-volts conversion 1ev = 1.602 × 10-19 j. the rest mass of an electron is 9.11 × 10 − 31 9.11 × 10 − 31 kg

Ben(55 kg) is standing on very slippery ice when junior(25kg) bumps into him. junior was moving at a speed of 8m/s before the collision and ben and junior embrace after the collision. find the speed of ben and junior as they move across the ice after the collision .

Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

An object weigh 40n in air ,weigh 20n when submerged in water, and 30n when submerged in a liquid of unknown liquid density. what is the density of unknown of liquid?