英语听力 学英语,练听力,上听力课堂! 注册 登录
> 在线听力 > 英语初级听力 > 科普英语 Earth and Sky >  第1篇

Earth and Sky科普英语: Black and White 黑与白

所属教程:科普英语 Earth and Sky

浏览:

手机版
扫描二维码方便学习和分享
https://online2.tingclass.net/lesson/shi0529/0008/8879/1.mp3
https://image.tingclass.net/statics/js/2012
Sometimes you hear it said that white is a combination of all the colors of the rainbow -- and that black is the absence of color. Find out more about whether black and white are colors -- today on Earth and Sky.

JB: This is Earth and Sky. A listener wants to know, "Are black and white really colors?"

DB: Color isn't a physical quality. It's a phenomenon of light and perception. Matter and energy are colorless. It's really our eyes and brains that make a fire-engine red or chickens white.

JB: Colors are defined by their hue, saturation, and value. Hue is what we think of as making blue blue, and not orange or grey. Saturation refers to a color's vividness -- it's what makes a pale blue sky different from one that's deep blue -- or pink different from red. Value refers to a colored object's lightness, darkness, and brightness -- that's the contrast between, say, the shining moon and a glass of red wine.

DB: It gets pretty complicated to talk about what makes a color a color -- because colors can only be talked about in terms of themselves -- and how they differ from one another. Black is black precisely because it has no redness or greenness or any other hue. But, to answer your question, black and white -- and grey, for that matter, too -- are colors. They're neutral colors -- different from each other only in terms of their darkness and lightness. Like all colors, black and white are products of our visual processes -- they exist only because we're there to sense them.

JB: To ask us your question, come to earthsky.org. With thanks to the National Science Foundation, we're Block and Byrd for Earth and Sky.

用户搜索

疯狂英语 英语语法 新概念英语 走遍美国 四级听力 英语音标 英语入门 发音 美语 四级 新东方 七年级 赖世雄 zero是什么意思惠州市绿雅居英语学习交流群

网站推荐

英语翻译英语应急口语8000句听歌学英语英语学习方法

  • 频道推荐
  • |
  • 全站推荐
  • 推荐下载
  • 网站推荐