Maslow's Hierarchy of Needs. Definition. Maslow's hierarchy of needs is a theory of motivation and personality developed by the psychologist Abraham H. Maslow (1908â1970). Maslow's hierarchy explains human behavior in terms of basic requirements for survival and growth.
When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice!).
1 [anno: In the process of making ice cream, the freezing point of the ice is lowered by the presence of the rock salt. 2  This allows the ice to absorb a lot of heat from the cream mixture without melting. 3  When enough heat has been absorbed from the cream mixture, the water in the cream mixture begins to freeze rapidly.].