Classical Physics

Matter is anything that occupies space and has mass. It exists in three basic forms. Plasma—highly ionized gas—has been called a fourth form.Classical physics is based primarily on the laws of motion and gravitation of Sir Isaac Newton and the theory of electromagnetic radiation of James Clerk Maxwell. In classical physics matter and energy are two separate concepts.
Energy is the capacity to move matter; as more commonly stated, it is the capacity to do work. Energy exists as mechanical energy, chemical energy, radiant energy, and nuclear energy. Radiant energy, which travels in waves, includes electricity and light and other forms of electromagnetic radiation, such as radio waves.
Some of the most important laws in classical physics are the conservation laws. The law of conservation of mass states that matter cannot be created or destroyed. The law of conservation of energy states that energy cannot be created or destroyed. The law of conservation of momentum states that the momentum of an object is unchanged unless a force acts on it.
Classical physics is usually divided into several branches, each of which deals with a group of related phenomena. Mechanics is the study of forces and their effect on matter. Dynamics is the study of change in motion because of force. Hydromechanics is the mechanics of fluids; that is, of liquids and gases. Hydromechanics is also known as fluid mechanics. Statics deals with how force affects bodies in constant motion and moving in a constant direction. Optics is the study of the behavior of light. Thermodynamics is the study of heat, and how heat energy is stored, transmitted, and converted to other forms of energy. Acoustics is the study of sound. The study of electricity and magnetism also forms a branch of classical physics.