要約
30 秒でわかる
This short introduction explains how light changes direction in glass and why different frequencies separate in a prism.
- 1Light in glassLight travels more slowly in glass than in vacuum.
- 2RefractionA beam entering at an angle changes direction.
- 3DispersionDifferent frequencies bend differently and separate.
ポイント
- Light changes direction at an interface when it enters at an angle.
- Glass slows different frequencies by different amounts.
- White light contains components with different spectral colors.
トピックPhysics
全文
チャプターごとに整えた全文を読む
01
Refraction and dispersion
The speaker introduces how a prism separates white light.
The speaker starts with a common explanation of a prism: light travels more slowly in glass, and a beam entering the glass at an angle changes direction, a phenomenon called refraction.
White light can be represented as a mixture of different frequencies, corresponding to spectral colors. Glass affects their speeds differently, so they refract by different amounts and spread into a rainbow.
同じチャンネルの記事
40:44EN
3Blue1Brown· 2026年10月16日Grant Sanderson: There's never been a better time to go into mathGrant Sanderson, Constantin Kogler · 3Blue1BrownStudents fear AI has solved mathematics. Grant Sanderson argues the opposite: even if machines prove theorems better than we do, the institution of math stays valuable—and this is a rare moment when newcomers can reshape it.
51:55EN3Blue1Brown· 2026年9月18日The last IMO problem AI could not solveGrant Sanderson · 3Blue1BrownGrant Sanderson walks through IMO 2025 Problem 6 — a tiling puzzle that frontier models missed — and the visual patience it takes to prove a construction is optimal.
0:55EN3Blue1Brown· 2026年7月24日The 64 Sugar Cubes Puzzle: Six Equal DistancesA 4×4×4 block has three colors; prove that six same-colored pairs share a distance.
33:51EN3Blue1Brown· 2026年7月16日What Cross-Entropy Connects: Compression, Language Models and KL DivergenceGrant Sanderson · 3Blue1BrownGrant Sanderson builds cross-entropy from code lengths and uses it to explain next-token training and distillation.
2:25EN3Blue1Brown· 2026年6月12日How Shannon Measured the Entropy of EnglishA guessing game helped Claude Shannon estimate how much information English text contains, and why prediction is central to compression.
1:02EN3Blue1Brown· 2026年6月10日A Robot Walk and the Puzzle of Optimal Binary EncodingHow few bits does it take to send directions that occur with unequal frequencies?