M mass of the body. It can be computed using the equation K ½mv² where m is mass and v is speed. Gravitational potential energy derivation.
Ek is the energy of a mass m in motion v2.
Ek 12 mv2 Ek Kinetic energy. V is the speed in metres per. Kinetic energy is the energy of motion. As m g and d will be constant between equations the greatest work done by friction will belong to the car with the greatest mass.