Answer the following question given this paragraph: 4.4 Newton's Third Law of Motion: Symmetry in Forces There is a passage in the musical Man of la Mancha that relates to Newton's third law of motion. Sancho, in describing a fight with his wife to Don Quixote, says, "Of course I hit her back, Your Grace, but she's a lot harder than me and you know what they say, 'Whether the stone hits the pitcher or the pitcher hits the stone, it's going to be bad for the pitcher. '" This is exactly what happens whenever one body exerts a force on anotherthe first also experiences a force (equal in magnitude and opposite in direction). Numerous common experiences, such as stubbing a toe or throwing a ball, confirm this. It is precisely stated in Newton's third law of motion. Newton's Third Law of Motion Whenever one body exerts a force on a second body, the first body experiences a force that is equal in magnitude and opposite in direction to the force that it exerts. This law represents a certain symmetry in nature: Forces always occur in pairs, and one body cannot exert a force on another without experiencing a force itself. We sometimes refer to this law loosely as "action-reaction," where the force exerted is the action and the force experienced as a consequence is the reaction. Newton's third law has practical uses in analyzing the origin of forces and understanding which forces are external to a system. We can readily see Newton's third law at work by taking a look at how people move about. Consider a swimmer pushing off from the side of a pool, as illustrated in Figure 4.9. She pushes against the pool wall with her feet and accelerates in the direction opposite to that of her push. The wall has exerted an equal and opposite force back on the swimmer. You might think that two equal and opposite forces would cancel, but they do not because they act on different systems. In this case, there are two systems that we could investigate: the swimmer or the wall. If we select the swimmer to be the system of interest, as in the figure, then F wall on feet is an external force... Q: Newton's third law of motion describes what property of forces that means balance? Choices: - acceleration - magnetism - gravity - symmetry A:
symmetry
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Answer the following question given this paragraph: What is one of the most important characteristics of a referee? A referee must be neutral. He can't favor one team over the other. In chemistry, being neutral means not being an acid or a base. Pure water is an example of a neutral substance. In some chemical reactions, an acid and a base combine to form neutral products, including water. You'll see how this happens when you read this article. Q: What do you call a substance that is not an acid or a base? Choices: - equivalent - toxic - oxidic - neutral A:
neutral
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Answer the following question given this paragraph: Like water in the ocean, air in the atmosphere exerts pressure that increases with depth. Most gas molecules in the atmosphere are pulled close to Earth's surface by gravity. As a result, air pressure decreases quickly at lower altitudes and then more slowly at higher altitudes. This is illustrated in Figure below . Air pressure is greatest at sea level, where the depth of the atmosphere is greatest. At higher altitudes, the pressure is less because the depth of the atmosphere is less. For example, on top of Mount Everest, the tallest mountain on Earth, air pressure is only about one-third of the pressure at sea level. At such high altitudes, low air pressure makes it hard to breathe and is dangerous to human health. Q: Most gas molecules in the atmosphere are pulled close to earth's surface by what force? Choices: - weight - light - traction - gravity A:
gravity
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Answer the following question given this paragraph: There are only about 6200 known species of amphibians. They are placed in three orders: frogs, salamanders, and caecilians. Table below shows a picture of an amphibian in each order. It also provides additional information about the orders. Q: What are the 3 orders of amphibians? Choices: - bees, caddisflies, antilions - monotremata, artiodactyla, rodentia - hagfish, lampreys, acanthodii - frogs, salamanders, caecilians A:
frogs, salamanders, caecilians
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