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English for students of Physics_Unit 7

There is no gravitational pull . . . only a push! This hypothesis provides a general model for the mechanics of gravitation. It in no way refutes the observed behavior of gravitation, but merely seeks to explain it. I have based all but a single aspect of this model on established scientific knowledge, and that single aspect is my prediction of an unknown. (So it remains to be proved or disproved.) The team of medieval physicists stepped out of the time machine and began to examine the strange, new device fastened to the window. They had never before seen a. | 19 Unit Seven GRAVITATION READING PASSAGE There is no gravitational pull . . . only a push This hypothesis provides a general model for the mechanics of gravitation. It in no way refutes the observed behavior of gravitation but merely seeks to explain it. I have based all but a single aspect of this model on established scientific knowledge and that single aspect is my prediction of an unknown. So it remains to be proved or disproved. The team of medieval physicists stepped out of the time machine and began to examine the strange new device fastened to the window. They had never before seen a suction cup so with great enthusiasm they began to experiment by pulling this mysterious device off the window then reattaching it. The glass must attract the device remarked one of them. They all nodded in agreement. Next they found a smaller piece of glass and discovered that the suction cup had the gripping power to suspend it. This new revelation prompted another physicist to remark The device must also attract the glass Having no real reason to seek a better explanation than this for their observations the team of medieval physicists unanimously concurred and a new theory was born The device and the glass are attracted one to another this being a characteristic of space My comparison to medieval science is not an insult to physicists. I merely wish to emphasize mankind s present level of ignorance of the mechanics of our universe. We now know that the suction cup in this example is held to the glass by air pressure. The invisible molecules that make up air constantly bombard the surfaces of the glass and the suction cup. The difference in pressure cause what appears to be an attraction. My gravitational hypothesis is somewhat similar. All I ask of you the reader is to keep an open yet discerning mind. From http physicsweb.org EADING COMPREHENSION Exercise 1 Answer the following questions by referring to the reading passage 1. What does the writer mean by this hypothesis .