The refractive index of an unknown liquid

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SUMMARY

The refractive index of an unknown liquid condensing on dense flint glass with a known index of refraction of 1.655 can be determined using the principle of total internal reflection. The minimum angle of incidence for total internal reflection at the glass-liquid interface is 53.7 degrees. To find the refractive index of the unknown liquid, the equation for total internal reflection, n(1) * sin(theta) = n(2) * sin(90), is applied. The discussion emphasizes the importance of using relevant equations and suggests creating a ray diagram to visualize the problem.

PREREQUISITES
  • Understanding of the refractive index and its calculation
  • Familiarity with total internal reflection principles
  • Basic knowledge of ray diagrams in optics
  • Proficiency in using equations related to light propagation in different media
NEXT STEPS
  • Calculate the refractive index of the unknown liquid using the total internal reflection equation
  • Explore the concept of critical angle and its application in optics
  • Learn about ray diagrams and their role in understanding light behavior at interfaces
  • Investigate the effects of varying indices of refraction on light transmission and reflection
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Students and professionals in physics, particularly those studying optics, as well as educators looking for practical examples of refractive index calculations and total internal reflection concepts.

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A light ray in dense flint glass that has an index of refraction of 1.655 is incident to the glass surface. An UNKNOWN liquid condenses on the glass's surface. Total internal reflection on the glass-liquid interface occurs for a minimum angle of incidence on the glass-liquid interface at 53.7 degrees.

1. what is the refractive index of the unknown liquid?
2. if the liquid is removed, what is the minimum angle of incidence for total internal reflection?
3. for the angle of refraction of the ray into the liquid film?
4. Does a ray emerge from the liquid film into the air above?

assume the glass and liquid have parallel planar surfaces


Homework Equations


speed of light: c=299792458 m/s
planck's constanct: h=6.626*10^-34 J*s= 4.136*10^-15 eV*s
transportation in a medium: v= c/n where n= the index of refraction
index of refraction: n=c/v
total internal reflection: n(1)*sin(theta)(c)=n(2)*sin(90) where n(1)>n(2)
Malus' law: I=I(0)*cos^2(theta)

The Attempt at a Solution



I used the above equations to determine the refractive index of the liquid, but I was getting very odd/ unrealistic answers.
Can you walk me through the problem/ explain what I should do for each step?

[/B]
 
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many questions said:
1.

A light ray in dense flint glass that has an index of refraction of 1.655 is incident to the glass surface. An UNKNOWN liquid condenses on the glass's surface. Total internal reflection on the glass-liquid interface occurs for a minimum angle of incidence on the glass-liquid interface at 53.7 degrees.

1. what is the refractive index of the unknown liquid?
2. if the liquid is removed, what is the minimum angle of incidence for total internal reflection?
3. for the angle of refraction of the ray into the liquid film?
4. Does a ray emerge from the liquid film into the air above?

assume the glass and liquid have parallel planar surfaces


Homework Equations


speed of light: c=299792458 m/s
planck's constanct: h=6.626*10^-34 J*s= 4.136*10^-15 eV*s
transportation in a medium: v= c/n where n= the index of refraction
index of refraction: n=c/v
total internal reflection: n(1)*sin(theta)(c)=n(2)*sin(90) where n(1)>n(2)
Malus' law: I=I(0)*cos^2(theta)

The Attempt at a Solution



I used the above equations to determine the refractive index of the liquid, but I was getting very odd/ unrealistic answers.
Can you walk me through the problem/ explain what I should do for each step?
[/B]
Which of "the above equations" did you use and how? Several of them are totally irrelevant. I suggest that you draw a ray diagram under the conditions described (ray incident at minimum angle of incidence) and then apply one of the above equations that is appropriate to the diagram.
 

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