第1个回答 2010-11-20
One day, Newton sitting under the apple tree, reading, suddenly, an apple fell out. Newton thought: "why apple will fall down? Everything will be falling? What can stop objects fall? The sun, the moon and the stars will fall?" With these questions, Newton did a lot of experiments, eventually found "the law of universal gravitation".
第2个回答 2010-11-20
One day, Newton was reading the book under an apple tree. Suddenly, an apple dropped from the tree. Newton wondered that why the apple dropped, which could prevent the object dropping and the Sun, Moon and star also dropped? Newton done many experiment with these questions. and found 'the law of universal gravitation