1. The problem statement, all variables and given/known data A piece of an empty rocket booster fuel tank (mass 45 kg) is ejected from a rocket that is 2100 km above the Earth's surface. It is travelling upwards at 4.5km/s at this time. a) what is the total energy of the booster at this time? b) Will it return to earth? 2. Relevant equations Total mechanical energy = ½mv^2 - GMm / r 3. The attempt at a solution for a, should i use kinetic and potential energy and plug in values? like find the total mechanical energy and for b, you find the total mechanical energy if you didnt have to do that for a, then if the value is positive it won't return to earth but if its negative, it will.