Compressed air car The principal disadvantages are the steps of energy conversion and transmission, because each inherently has loss. For combustion engine cars, the energy is lost when chemical energy in fossil fuels is converted by the engine to mechanical energy. For electric cars, a power plant's electricity (from whatever source) is transmitted to the car's batteries, which then transmits the electricity to the car's motor, which converts it to mechanical energy. For compressed-air cars, the power plant's electricity is transmitted to a compressor, which mechanically compresses the air into the car's tank. The car's engine then converts the compressed air to mechanical
Potential energy the gravitational potential, often denoted by formula_47 or formula_48, corresponding to the energy per unit mass as a function of position. The gravitational potential energy of two particles of mass "M" and "m" separated by a distance "r" is The gravitational potential (specific energy) of the two bodies is where formula_51 is the reduced mass. The work done against gravity by moving an infinitesimal mass from point A with formula_52 to point B with formula_53 is formula_54 and the work done going back the other way is formula_55 so that the total work done in moving from A to B