«Amazing physics» 9 сыныпқа арналған
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| Associations to the word
«Gravity» - Write two sentences about this word. (Students write their association ideas about gravity and discuss in pairs) - Today you will work in pairs. Read the text and discuss with your partner. Ask each other for opinions. Gravity, also called gravitation, in mechanics, the universal force of attraction acting between all matter. It is by far the weakest known force in nature and this plays no role in determining the internal properties of everyday matter. On the other hand, through its long reach and universal action, it controls the trajectories of bodies in the solar system and elsewhere in the universe and the structures and evolution of stars, galaxies, and the whole cosmos . On Earth all bodies have a weight , or downward force of gravity, proportional to their mass, which Earth’s mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At Earth ’s surface the acceleration of gravity is 53 about 9.8 metres (32 feet) per second per second. Thus, for every second an object is in free fall, its speed increases by about 9.8 metres per second. At the surface of the Moon the acceleration of a freely falling body is about 1.6 metres per second per second. The works of Isaac Newton and Albert Einstein dominate the development of gravitational theory. Newton’s classical theory of gravitational force held sway from his Principia, published in 1687, until Einstein’s work in the early 20th century. Newton’s theory is sufficient even today for all but the most precise applications. Einstein’s theory of general relativity predicts only minute quantitative differences from the Newtonian theory except in a few special cases. The major significance of Einstein’s theory is its radical conceptual departure from classical theory and its implications for further growth in physical thought. - Today we will take some new terms. Please, repeat after me. First listen, and then repeat. Say it with me. Keep going. жүктеу/скачать 3.19 Mb. Достарыңызбен бөлісу:
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