Electric chargeElectric charge is a property of many standard model particles, including the electron. This property makes them feel a force from other charged particles. Electrical charge can be either negative or positive, with negatively charged particles attracting positively charged ones while repelling their own kind. The unit of electric charge is called the coulomb [C]; 1 coulomb is the charge transported per second by an electric current of 1 ampere. The negative charge of an electron is -1.602 x 10~19C. For simplicity, the electron charge is often denoted as -1, while that on a positively charged proton is +1. Electric charge plays a pivotal role in our very existence, allowing solid structures like the Earth, buildings and animals to exist. Atoms are mostly empty space, but they don't fall through each other due to repulsion between electrons in neighbouring atoms. Charged particles zinging around in the Sun's atmosphere also play a crucial role by generating the radiation that keeps our planet's surface warm and hospitable.
Magnetism is a property of materials that makes them experience a force in a magnetic field. It explains why iron filings line up in ordered patterns near a bar magnet for instance, and why fridge magnets stick to fridges. Bar magnets are strips of magnetized metal, usually iron, that form a «dipole" field with a north and south pole. Opposite poles attract each other, while like poles repel. The magnetic field of a permanent magnet arises because electrons inside it generate their own tiny magnetic fields due to an intrinsic property called spin, and in materials like iron, the spins of unpaired electrons tend to line up. Scientists have known since the early 1800s that there is a deep connection between magnetism and electric current. For instance, an electric current flowing through a coil of wire creates a dipole magnetic field similar to that of a bar magnet. Modern electromagnets have achieved record-breaking magnetic fields of 35 teslas, where 1 tesla is about 20,000 times stronger than the Earth's magnetic field.
2. On the lines below, write either the abbreviation or the whole word that matches. 1. __________________ = MHz 2. hertz = __________________ 3. __________________ = min. 4. kilohertz = _______________ 5. __________________ = oz. 6. __________________ = ft. 7. quart = __________________ 3.Continue the list with the units presented in the texts above, explain them.
4.Translate from Russian into English: 1. Использование электрической энергии изменило весь наш образ жизни. 2. Чтобы понимать действие различных электрических машин и приборов, мы должны знать основные законы электричества. 3. Вещества, проводящие электричество, называются проводниками. 4. Вещества, не проводящие электричество, называются изоляторами. 5. Два положительно заряженных предмета отталкивают друг друга 6. Любой положительно заряженный предмет притягивает любой отрицательно заряженный предмет. 7. Электроскоп представляет собой прибор для обнаружения присутствия электрического заряда. 8. Существует закон, управляющий всеми явлениями природы. Этот закон называется законом сохранения энергии. 9. Существует много различных форм энергии. 10. Существуют кинетическая энергия, тепловая, электрическая, химическая, ядерная и энергия излучения.
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