I want to know whether every kind of energy is converted to mass like kinetic and potential energy? Is it only possible for particles like electionselectrons and protons ouror even either for big objects like a car or bus. Please consider the minutest / smallest change in mass even 0.000000000000000000000001 kg of gain in mass? I mean "relativistic mass" in case when the object is moving and "rest mass" in case when the object is at rest. Can Rest mass too can increase when the gravitational potential energy of an object increases