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Why Frisbees Fly With a gentle flick of the wrist on a warm summer day, you can launch a frisbee on a long and graceful flight. Why do they fly so well? One reason is something called gyroscopic force. This is the tendency of a spinning object to mai
发表于:2019-03-09 / 阅读(99) / 评论(0)
英语听力文摘 English Digest
英语听力文摘 English Digest