사라지는 비커(굴절률 매칭)

굴절률이 일치하는 액체에 담가 유리 물체 투명하게 만들기

Classroom Demonstrations Beginner (Middle School) 15 분 ~$8.00

목표

유리 물체를 굴절률이 일치하는 액체 속에서 사라지게 만들어 굴절률의 개념을 실증한다.

배경

We see transparent objects like glass because light bends (refracts) at the surface where the glass meets air. The degree of bending depends on the difference in refractive index between the two media. If a glass object is placed in a liquid with the same refractive index, light passes through without bending, and the object becomes effectively invisible. Pyrex glass (n ≈ 1.474) nearly matches vegetable oil (n ≈ 1.47), creating a stunning visual effect.

안전 경고

  • Vegetable oil is slippery — clean up spills immediately to prevent falls
  • Glass objects can break — handle with care

필수 개인 보호 장비

goggles

재료

  • Vegetable oil (or glycerol) (500 mL)
    Refractive index ≈ 1.47
  • Pyrex glass beaker or rod (1)
    To disappear
  • Regular glass rod (1)
    For comparison (different n)

장비

Large glass beaker (1 L) or clear container

실험 절차

1

Fill the large beaker about 2/3 full with vegetable oil.

2 분
2

Show the Pyrex glass object to the audience. Note that it is clearly visible in air.

1 분
3

Slowly lower the Pyrex glass into the vegetable oil. As it submerges, it gradually becomes invisible.

3 분 Lower gently to avoid splashing
4

For comparison, lower the regular glass rod into the same oil. It remains visible because its refractive index does not match.

3 분
5

Discuss: light refracts at boundaries between materials with different refractive indices. When n values match, no refraction occurs and the object seems to disappear.

6 분

예상 결과

The Pyrex glass becomes nearly invisible when submerged in vegetable oil. Only slight distortions at the edges may be visible. The regular glass rod remains clearly visible in the same oil.

정리

Remove glass objects and wash with dish soap. Oil can be saved for reuse or disposed of in general waste. Wipe up any oil spills.

세부 정보

카테고리
Classroom Demonstrations
난이도
Beginner (Middle School)
소요 시간
15 분
예상 비용
$8.00
단계
5
재료
3

더 많은 실험

드라이아이스 속 마그네슘 연소 25 min 진동하는 브릭스-라우처 반응 40 min 나트륨과 물의 반응 25 min 아이오딘 시계 반응 45 min 코끼리 치약 20 min 테르밋 반응 30 min 루미놀 화학발광 30 min 비뉴턴 유체: 우블렉 20 min 밀도 컬럼 무지개 30 min 순간 냉동: 과냉각수 120 min

Frequently Asked Questions

What is the objective of 사라지는 비커(굴절률 매칭)?
유리 물체를 굴절률이 일치하는 액체 속에서 사라지게 만들어 굴절률의 개념을 실증한다.
How difficult is 사라지는 비커(굴절률 매칭)?
This experiment is rated as Beginner (Middle School). It takes approximately 15 minutes to complete.
What safety precautions are needed for 사라지는 비커(굴절률 매칭)?
Key safety precautions include: Vegetable oil is slippery — clean up spills immediately to prevent falls; Glass objects can break — handle with care.
What materials are needed for 사라지는 비커(굴절률 매칭)?
The main materials required are: Vegetable oil (or glycerol), Pyrex glass beaker or rod, Regular glass rod.
What results should I expect from 사라지는 비커(굴절률 매칭)?
The Pyrex glass becomes nearly invisible when submerged in vegetable oil. Only slight distortions at the edges may be visible. The regular glass rod remains clearly visible in the same oil.