«Amazing physics» 9 сыныпқа арналған
II. Division for groups
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II. Division for groups The students are dividing in advance into three groups. They are divided into three groups. III. Learning material I. Activity. Reading We said earlier that there are mysterious forces that can push or pull things without touching them. This is called force at a distance. The force at a distance you feel must often is the force of gravity. The force of gravity is an attraction between any two things made of matter. Every bit of matter in the world is attracted to every other bit of matter. read the text and discuss in groups; 70 You may remember that gravity only pulls; it never pushes. Maybe you are wondering why you don’t see everything being pulled together. Most things don’t stick to you, and you can’t feel yourself pulled toward other people. The reason is that gravity is a very weak force. We don’t notice gravity unless something has a lot of mass. The Earth is something with a lot of mass. Earth’s gravity pulls everything toward it. It pulls on you so hard that you can only jump a few feet above the Earth before gravity pulls you back. When we use the word “down” we mean “the direction that gravity pulls”. The more mass two things have the stronger will be the force of gravity pulling them together. The farther apart two things are, the weaker will be the force of gravity pulling them together. P – weight of body P = m • g Weight being a force, the SI unit is Newton. m – mass of the body жүктеу/скачать 3.19 Mb. Достарыңызбен бөлісу:
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