Blackbody Radiation · 黑体辐射
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| blackbody radiation/ˈblækbɒdi ˌreɪdɪˈeɪʃn/ | 黑体辐射 | hēi tǐ fú shè |
Heat metal and it glows red, then orange, then white
- A cool poker is dark; heat it and it glows a dull red, then orange, then dazzling white.
- Every warm object glows — the colour tells you its temperature.
- This glow is blackbody radiation 黑体辐射, given off by all hot bodies.
- Explaining its shape needed a brand-new idea — the birth of quantum theory.
加热金属,它先发红,然后橙,再到白
- 凉的火钳是暗的;加热它,它先发暗红,然后橙,再到耀眼的白。
- 每个温热的物体都发光——颜色告诉你它的温度。
- 这种发光是黑体辐射,所有热物体都发出它。
- 解释它的形状需要一个全新的想法——量子理论的诞生。
The radiation curve
- A hot body emits a smooth spread of wavelengths, with a clear peak.
- Plot intensity against wavelength and you get a curve that rises to a peak, then falls.
- A hotter body glows brighter (a taller curve) at every wavelength.
- Its peak also shifts to a shorter wavelength — from red toward blue.
辐射曲线
- 热物体发出一段平滑的波长分布,有一个清晰的峰。
- 把强度对波长作图,你得到一条升到峰再下降的曲线。
- 更热的物体在每个波长上都发光更亮(曲线更高)。
- 它的峰也移向更短的波长——从红移向蓝。
As a blackbody gets hotter, its peak wavelength: · 随着黑体变热，其峰值波长：
A hotter body peaks at a shorter wavelength — the glow shifts toward blue. · 较热的物体在较短波长处达到峰值——发光向蓝色偏移。
A hotter blackbody emits more intensity at every wavelength than a cooler one. · 较热的黑体在每个波长处的发射强度都高于较冷的黑体。
The hotter curve is taller at all wavelengths. · 较热的曲线在所有波长处都更高。
Colour tells temperature
- Because the peak shifts with temperature, the colour of the glow reveals how hot something is.
- A red star is cooler; a blue-white star is hotter (the opposite of the "hot = red" everyday feel).
- Astronomers judge a star's temperature from the colour of its light.
- Even your own body glows — in the infrared, which thermal cameras see.
颜色告诉温度
- 因为峰随温度移动,发光的颜色揭示了物体有多热。
- 红色的恒星更冷;蓝白色的恒星更热(与"热 = 红"的日常感觉相反)。
- 天文学家从恒星光的颜色判断它的温度。
- 甚至你自己的身体也发光——在红外,热成像相机能看到。
A red star and a blue-white star: which is hotter? · 一颗红色恒星和一颗蓝白色恒星：哪颗更热？
Blue-white light peaks at a shorter wavelength, so that star is hotter. · 蓝白光在较短波长处达到峰值，因此该恒星更热。
The colour of a glowing object can be used to estimate its temperature. · 发光物体的颜色可用于估算其温度。
The peak wavelength (colour) shifts with temperature, so colour reveals it. · 峰值波长（颜色）随温度变化，因此颜色揭示了温度。
Select all · 所有 true statements about blackbody radiation. · 选择关于黑体辐射的所有正确陈述。
Hotter = brighter, peak bluer, colour = temperature. Classical physics failed; Planck's quanta were needed. · 较热=更亮，峰值更蓝，颜色=温度。经典物理学失败；需要普朗克的量子。
Why it launched quantum theory
- Classical physics predicted a hot body should blast out infinite ultraviolet energy — clearly wrong.
- Max Planck fixed it by assuming energy comes in quanta (packets), $E = hf$.
- That single quantum assumption gave the correct curve — and started quantum physics.
- Blackbody radiation is where the quantum world first announced itself.
它为何开启了量子理论
- 经典物理预测热物体应当放出无穷大的紫外能量——显然错了。
- 马克斯·普朗克通过假设能量以量子(小包)出现来修正它,$E = hf$。
- 那一个量子假设给出了正确的曲线——并开启了量子物理。
- 黑体辐射是量子世界第一次宣告自己存在的地方。
Hotter or cooler blackbody? · 更热还是更冷的黑体？
A blackbody's spectrum shifts with temperature. Sort each fact. · 黑体的光谱随温度变化。对每个事实进行分类。
Planck explained the blackbody curve by assuming energy comes in packets called ____. · 普朗克通过假设能量以称为 ____ 的包络形式出现来解释黑体曲线。
Energy quanta ($E = hf$) gave the correct curve and started quantum theory. · 能量量子 ($E = hf$) 给出了正确的曲线并开启了量子理论。
For a hotter body, the peak shifts to a shorter wavelength (toward blue), not a longer one. This is the reverse of everyday intuition where "hot = red". A blue-white star is much hotter than a red one.
对更热的物体,峰移向更短的波长(向蓝),而非更长。这与"热 = 红"的日常直觉相反。蓝白色的恒星比红色的热得多。
Two stars glow, one red and one blue-white. Which is hotter?
- The blue-white star is hotter — its blackbody peak is at a shorter wavelength.
- The red star is cooler, with its peak toward longer wavelengths.
两颗恒星发光,一红一蓝白。哪个更热?
- 蓝白色的恒星更热——它的黑体峰在更短的波长处。
- 红色的恒星更冷,峰移向更长的波长。
Blackbody radiation is the glow of every hot object. A hotter body is brighter and its peak shifts to a shorter wavelength (bluer) — so colour reveals temperature. Explaining the curve required Planck's idea that energy comes in quanta ($E = hf$), launching quantum theory.
黑体辐射是每个热物体的发光。更热的物体更亮,它的峰移向更短的波长(更蓝)——所以颜色揭示温度。解释这条曲线需要普朗克的想法:能量以量子出现($E = hf$),开启了量子理论。