The phase of matter is determined by the forces acting on the molecules and the energy associated with the substance. The phases or states of matter are solid, liquid, gas, and plasma. The Kinetic Theory states that molecules are in constant motion and undergo perfectly elastic collisions. The average kinetic energy of a particle is proportional to its temperature. The Gas Laws explain the relationships between pressure, volume, and temperature.
Many gases behave as ideal gases at moderate temperatures and pressures.
At low temperatures and high pressures deviations become very significant. The Nature of Waves Waves are very familiar phenomena. All waves have one property in common and that is they transfer energy. Sound waves bring music to our ears and light waves bring energy from the sun. There are two basic types of waves.