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The world and the Universe are action-packed.
People and animals are always on the move. The planets are constantly circling the Sun. Are there any rules to all this activity? Yes! Our world and the whole Universe are governed by the laws of nature. Scientists who try to understand and learn about these laws are called physicists. Here are some questions that physicists across history have wondered about: When you drop a ball, why does it fall on the ground? Why doesn’t it float up? If you spin a top, why doesn’t it spin forever? Why does it eventually stop? Maybe you have wondered about these things, too.
