物理学研究我們周圍物質世界的最普遍的特性及其規律。物理学的规律乃是整個自然界普遍的規律。例如万有引力定律,不論对於宏观世界的物体(如太陽、行星、恒星)來說,或是对於微观世界的物体(如原子和分子世界)來說都是同樣正確的。不管相互作用的物体是無生命世界的物体,或是有生命世界的物体,都是同樣遵从这個定律的。同樣,能量守恆和轉換定律对於任何閉合系統都是正確的,不管这個系統是由什么樣的物体構成的,也不管在这系統內發生的是什么过程:力学的,熱学的,化学的还是生物学的等等。这個定律,对於物 Physics studies the most common characteristics and laws of the physical world around us. The law of physics is a common law throughout nature. For example, the law of universal gravitation is equally valid for objects in the macroscopic world (such as the sun, planets, and stars), or for objects in the microscopic world (such as the atomic and molecular worlds). Whether interacting objects are inanimate world or in living world, the same is true of this law. Similarly, the law of conservation and conversion of energy is correct for any closed system, regardless of what kind of object the system is made of and regardless of what happens in the system: Mechanics, Thermal, Chemistry Or biology and so on. This law, for the thing