A. three hundred thousand B. three hundreds thousand C. three hundred thousands D. three hundreds thousands of 相关知识点: 试题来源: 解析 A。“hundred”“thousand”等词,前面有具体数字时,不用复数形式,也不能加“of”,所以“三百千米”是“three hundred thousand kilometers”。
将“光所拥有的速度”视为像车速一样物理量一样时，它就可以有不同的测量精度版本，另外光在不同介质中的速度也确实不一样，所以可以有a speed of light，比如 【例句1】Romer calculated a speed of light of around 220,000 kilometers per second. (罗默计算出的光速约为每秒22万公里。)对a speed of ...
A. 300,000 kilometers per second B. 300,000 meters per second C. 30,000 kilometers per second D. 3,000 kilometers per second 相关知识点: 试题来源: 解析 A。光的速度约为 300,000 千米每秒,这是科学常识,B 选项 300,000 米每秒速度太慢,C 选项 30,000 千米每秒和 D 选项 3,000 千米...
The speed of light is 300,000 kilometers per second, and the sun is 150 million kilometers away from the earth. Q: How many minutes does it take for light to travel from the Sun to Earth (one decimal place is reserved)?相关知识点: 试题来源: ...
A. per second B. every second C. in second D. on second 相关知识点: 试题来源: 解析 A。本题考查物理单位的表达。“per second”表示“每秒”,符合速度单位的表达。“every second”意为“每一秒”,但不是速度单位的表达。“in second”和“on second”都是错误的表达。
The scientific research showed that the speed of light is ___. A. 300,000 kilometers per second B. 100 kilometers per hour C. 50 meters per minute D. 20 feet per second 相关知识点: 试题来源: 解析 A。科学研究表明光的速度是 300000 千米每秒,其他选项的速度都不是光的速度。
The speed of light in vacuum is approximately 300,000 kilometers per second. Which of the following statements is correct about the speed of light? A. It is always the same regardless of the medium. B. It is slower in air than in vacuum. C. It is faster in water than in vacuum. ...
What is the speed of light? A. 300,000 kilometers per second. B. 300,000 meters per second. C. 30,000 kilometers per second. D. 30,000 meters per second. 相关知识点: 试题来源: 解析 A。光的速度是 30 万千米每秒,所以答案是 A。B、C、D 选项的速度都不对。
A. 300,000 kilometers per second B. 200,000 kilometers per second C. 100,000 kilometers per second D. 400,000 kilometers per second 相关知识点: 试题来源: 解析 A。解析:光的速度大约是 30 万千米每秒。B、C、D 选项的数值均不符合光的实际速度。
A. per B. in C. on D. at 相关知识点: 试题来源: 解析 A。本题考查“每……”的英语表达。“per”有“每”的意思,“300000 kilometers per second”表示“每秒 300000 千米”。“in”表示“在……里面”;“on”表示“在……上面”;“at”表示“在……(具体地点或时间点)”,都不符合题意。