The refractive index of an unknown liquid

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The discussion focuses on determining the refractive index of an unknown liquid that condenses on dense flint glass with a known refractive index of 1.655. Total internal reflection occurs at a minimum angle of incidence of 53.7 degrees at the glass-liquid interface. Participants are seeking guidance on how to apply relevant equations to find the refractive index of the liquid, the minimum angle for total internal reflection if the liquid is removed, the angle of refraction into the liquid, and whether a ray can emerge into the air. There is a suggestion to create a ray diagram to visualize the scenario and apply the appropriate equations effectively. Understanding the correct application of these principles is crucial for solving the problem accurately.
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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.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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