Physics
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Physics is one of Aristotle's theoretical studies, and is classified by him as the study of things in motion, and the nature of the motions of different things.
One classification Aristotle makes is the difference between natural motion and violent motion. Violent motion would be motion caused by an outside force, while natural motion would be an animal moving of its own accord or an inanimate object going to its “proper place”. To explain the falling of a stone to the ground, for instance, Aristotle wrote that an object always goes towards its proper place. A stone goes towards the earth, and water does as well, but a stone sinks through water because it has a closer connection to the earth than water does. Wood comes from earth, but floats in water, so Aristotle would have considered it a mixture of the elements earth and air. Likewise, air moves upward towards the sky, but fire does even more, because fire cuts up through the air.
Aristotle’s laws of motion are:
1. Heavier things fall faster, with the falling speed being proportional to the weight of the object.
2. The speed of the object depends inversely on how dense the substance the object is falling through is. That is, the same object will fall twice as fast through a substance that is half as dense.
From these conjectures, Aristotle concludes that a vacuum is impossible, because then objects would fall at infinite speeds. He also believed that the speed of an object in violent motion is proportional to the force applied.
One classification Aristotle makes is the difference between natural motion and violent motion. Violent motion would be motion caused by an outside force, while natural motion would be an animal moving of its own accord or an inanimate object going to its “proper place”. To explain the falling of a stone to the ground, for instance, Aristotle wrote that an object always goes towards its proper place. A stone goes towards the earth, and water does as well, but a stone sinks through water because it has a closer connection to the earth than water does. Wood comes from earth, but floats in water, so Aristotle would have considered it a mixture of the elements earth and air. Likewise, air moves upward towards the sky, but fire does even more, because fire cuts up through the air.
Aristotle’s laws of motion are:
1. Heavier things fall faster, with the falling speed being proportional to the weight of the object.
2. The speed of the object depends inversely on how dense the substance the object is falling through is. That is, the same object will fall twice as fast through a substance that is half as dense.
From these conjectures, Aristotle concludes that a vacuum is impossible, because then objects would fall at infinite speeds. He also believed that the speed of an object in violent motion is proportional to the force applied.