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- The study of the refraction of light. 屈光学研究光的折射
- When did the first measurement of the speed of sound take? 第一次测量声速是在什么时候？
- Refraction of light gives the above results. 光的折射会产生上述的结果。
- Every paragraph is a distillation of sound judgment. 每段话都是正确判断的结晶。
- 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。
- Characterized by high volume and intensity. Used of sound. 大声的以高音量和强烈为特征的。用于声音
- A Sonic Measuring Technique of Furnace Temperature Fields Taking into Account the Refraction of Sound Waves 考虑声波折射的声学锅炉温度场测量技术的研究
- Mach two equals twice the speed of sound. 二马赫相当于声速的二倍。
- His distinction of sound is excellent. 他辨别声音的能力很强。
- Our teacher has mutation of sounds suddenly. 我们的老师突然语音发生了变化。
- Wood is a poor conductor of sound. 木头是声音的不良导体。
- 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
- The percentage of sound seed is usually 2-10%. 其健壮的种子通常仅占2-10%25。
- Characterized by harmony of sound; melodious. 悦耳的声音和谐的；悦耳的
- Air is the common medium of sound. 空气是声音的普通介质。
- Having one direction along which double refraction of light does not take place. Used of a crystal. 单轴晶体的有一个方向的，沿此方向不发生光的双折射。用于晶体
- Loudness of sound may be measured. 声音的响度可以测量。
- The plane is flying at the velocity of sound. 飞机以音速飞行。
- The lower the frequency is ,the greater the refraction of a cave will be . 频率越低，波的折射率越强。
- At the risk of sounding ungrateful, I must refuse your offer. 我甘受拂逆盛情之嫌，也必须谢绝你的提议。
