Модуль 1 - Общие сведения, глаголы to be, to have, конструкция there is(are), времена группы Indefinite Active Voice (1096805), страница 11

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Amber is fossilized tree sap millions of years old and hashardened as hard as a stone.Around 600 BCE (Before the Common Era) Greeks noticed a strange effect: When rubbing "elektron"against a piece of fur, the amber would start attracting particles of dust, feathers and straw. No one paidmuch attention to this "strange effect" until about 1600 when Dr. William Gilbert investigated the reactionsof magnets and amber and discovered other objects can be made "electric."Gilbert said that amber acquired what he called "resinous electricity" when rubbed with fur. Glass,however, when rubbed with silk, acquired what he termed "vitreous electricity."He thought that electricity repeled the same kind and attracts the opposite kind of electricity.

Gilbert andother scientists of that time thought that the friction actually created the electricity (their word for theelectrical charge).In 1747, Benjamin Franklin in America and William Watson in England both reached the same conclusion.They said all materials possess a single kind of electrical "fluid." They didn't really know anything aboutatoms and electrons, so they called how it behaved a "fluid."They thought that this fluid can penetrate matter freely and couldn't be created or destroyed.

The two menthought that the action of rubbing (like rubbing amber with fur) moves this unseen fluid from one thing toanother, electrifying both.Franklin defined the fluid as positive and the lack of fluid as negative. Therefore, according to Franklin,the direction of flow was from positive to negative. Today, we know that the opposite is true. Electricityflows from negative to positive. Others took the idea even further saying this that two fluids are involved.They said items with the same fluid attract each other.

And opposite types of fluid in objects will makethem repel each other.All of this was only partially right. This is how scientific theories develop. Someone thinks of whysomething occurs and then proposes an explanation. It can take centuries sometime to find the real truth.Instead of electricity being a fluid, it is the movement of the charged particles between the objects... thetwo objects are really exchanging electrons.3. Активный словарь46.

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