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!).
It's a chain reaction of freezing-point depression. The freezing point of cream is depressed by the milk and sugar particles, and the freezing point of the water is depressed by the particles of salt. That's the point of ice cream.