Factory pattern should be used when: - a framework delegate the creation of objects derived from a common superclass to the factory - we need flexibility in adding new types of objects that must be created by the class. Along with singleton pattern the factory is one of the most used patterns.
In thermodynamics, the term exothermic process (exo- : outside) describes a process or reaction that releases energy from the system to its surroundings, usually in the form of heat, but also in a form of light (e.g. a spark, flame, or flash), electricity (e.g. a battery), or sound (e.g. explosion heard when burning hydrogen).
Exergonic reactions have a net release of energy, but they still require a small amount of energy input before they can proceed with their energy-releasing steps. This small amount of energy input necessary for all chemical reactions to occur is called the activation energy (or free energy of activation) and is abbreviated E A. Activation energy: Activation energy is the energy required for a reaction to proceed; it is lower if the reaction is catalyzed.