Jawaban:

Fluids

indo: cairan

Penjelasan:

Fluids (Liquids and Gases)

Liquids and gases are called fluids because they can be made to flow, or move. In any fluid, the molecules themselves are in constant, random motion, colliding with each other and with the walls of any container. The motion of fluids and the reaction to external forces are described by the Navier-Stokes Equations, which express a conservation of mass, momentum, and energy. The motion of solids and the reaction to external forces are described by Newton's Laws of Motion.

Any substance can occur in any phase. Under standard atmospheric conditions, water exists as a liquid. But if we lower the temperature below 0 degrees Celsius, or 32 degrees Fahrenheit, water changes its phase into a solid called ice. Similarly, if we heat a volume of water above 100 degrees Celsius, or 212 degrees Fahrenheit, water changes its phase into a gas called water vapor. Changes in the phase of matter are physical changes, not chemical changes. A molecule of water vapor has the same chemical composition, H2O, as a molecule of liquid water or a molecule of ice.

When studying gases , we can investigate the motions and interactions of individual molecules, or we can investigate the large scale action of the gas as a whole. Scientists refer to the large scale motion of the gas as the macro scale and the individual molecular motions as the micro scale. Some phenomenon are easier to understand and explain based on the macro scale, while other phenomenon are more easily explained on the micro scale. Macro scale investigations are based on things that we can easily observe and measure. But micro scale investigations are based on rather simple theories because we cannot actually observe an individual gas molecule in motion. Macro scale and micro scale investigations are just two views of the same thing.

(Boleh di translate :D)