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- When did the first measurement of the speed of sound take? 第一次测量声速是在什么时候？
- Airliners in service at present cannot fly faster than the speed of sound. 目前供使用的客运机飞行速度不能超过音速。
- Mach two equals twice the speed of sound. 二马赫相当于声速的二倍。
- A device for measuring the speed of sound in water. 速度计，速度表用于测量声音在水中的速度的仪器
- Newtonian speed of sound 牛顿声速
- The speed of light is faster than that of sound. 光速比音速要快。
- New planes can fly at the speed of sound. 新型飞机可以音速飞行。
- Modern planes top the speed of sound. 现代飞机超过音速。
- The new airplane flies at twice the speed of sound. 这架新型飞机以两倍于音速的速度飞行。
- The speed of sound in water is about four as great as in air. 声音在水中的速度是空气中的四倍左右
- The frequency, wave length and speed of sound are closely related. 频率、波长和声速三者是密切相关的。
- The frequency, wave length, and speed of sound are closely related. 频率，波长和声速三者是密切相关的。
- The speed of sound varies in solids,liquids and gases. 在固体、液体和气体中，声音的速度不一样。
- The speed of sound varies in solids, liquids and gases. 在固体、液体和气体中,声音的速度不一样。
- When did the first measurementof the speed of sound take? 第一次测量声速是在什么时候?
- If a plane is flying at Mach 2, it is flying at twice the speed of sound. 假如飞机以二马赫的速度飞行，那么它的速度就是音速的两倍。
- If a plane is flying at Mach 2,it is flying at twice the speed of sound. 假如飞机以二马赫的速度飞行，那么它的速度就是音速的两倍。
- The effect of finite-range force fot the speed of sound is very small. 有限力程部分对声速的影响很小。
- One quick side note: the speed of sound varies with the condition of the air. 从侧面可以知道：声音的速度受空气条件的影响而出现变化。
- This lets the gas escape and slows the bullet to below the speed of sound. 由此气体得以枪管里泄出，而子弹的速度也会降到音速以下。
