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- light travelling modulation 光行波调制
- Light travels faster than sound. 光比声音速度快。
- Does light travel out in one direction or in all directions? 光是沿着一个方向还是所有方向往外传播的？
- So fast does light travel that it is difficult for us to imagine its speed. 光传播得如此之快,以至于我们无法想像它的速度。
- So fast does the light travel that it is difficult for us to imagine its speed. 光传播的很快我们无法测量其速度。
- Light travels faster than anything else. 光跑得任何东西都快。
- Light travels about 300,000 kilometers per second. 光的速度大约每秒三十万公里。
- Can you tell me how fast light travels? 你能告诉我光速有多快吗?
- The same way as slow light travels. 和慢的光线一样传播。
- He said that light travels much faster than sound. 他说光比声音传播得快。
- Light travels at a speed of 300,000 km per second. 光以每秒30万千米的速度传播。
- The light travels faster than the sound. 光比声音的传播速度快.
- Light travels much faster than sound. 光的传导比声音快得多。
- Light travels in rectilinear form. 光以直线形式传播。
- Dr Hess envisages a ray of light travelling down an optical fibre made from two materials: a core with a negative refractive index and an outer sheath with a positive one. 赫斯博士构想出一个画面，即一道光正穿越于一个由两种材料制作的光导纤维，一种是具有阴性折射指数的纤维核，另一种则是具有阳性折射指数的外围。
- Light travels very fast. It moves at 300,000 kilometres a second. 光传播得很快，每秒钟300，000公里。
- In a uniform medium light travels in straight lines. 在均匀介质中光沿直线传播。
- In a hundredth of a second, light travels 3,000 kilometers. 在百分之一秒的时间里，光传播了3000千米。
- A light year is the distance which light travels at 186,000 miles per second in one year, namely 6 million million miles. 1光年是以每秒186000英里的速度走过一年的距离，约为6万亿英里。
- In a hundredth of a second,light travels 3,000 kilometers. 在百分之一秒的时间里，光传播了3000千米。
