Megaelectron-volts
A megaelectron-volt (MeV) is a unit of energy used in particle and nuclear physics. It is derived from the electron-volt (eV) - the amount of kinetic energy gained or lost by an electron when it moves through one volt.
Calories (I.T.)
The Calorie (I.T.) or International Table Calorie is defined as the amount of energy required to raise the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere which is approximately 4.1868 joules.