Finding critical angles and index of refractions

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To find the critical angle for a material with an index of refraction of 1.75, use the formula θ_critical = sin⁻¹(1/n), resulting in approximately 34.85 degrees. For cubic zirconium with a critical angle of 29.2 degrees, the index of refraction can be calculated as n = 1/sin(29.2º), yielding an index of about 2.05. Users are advised to set their TI-83 Plus calculator to degree mode by pressing [MODE] and selecting "Degree." The discussion also touches on shared experiences in online education. Understanding these calculations is essential for solving refraction problems effectively.
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im having trouble setting my TI-83 Plus into "degree mode" so i can't seem to get the answers for these problems...im probably doing them wrong too

A material has an index of refraction of 1.75. What is the critical angle for this material?

Sin(critical angle)=1/n, n being the index of refraction
how would i set up the formula? (critical angle)= Sin(n) ?? I am so confused

and

The critical angle for cubic zirconium is 29.2º. What is the index of refraction?

so...Sin(29.2º)= 1/n?...

my answer for this question is 2.049, rounded to 2.05

thank you,

mark
 
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mark9159 said:
im having trouble setting my TI-83 Plus into "degree mode" so i can't seem to get the answers for these problems...im probably doing them wrong too

A material has an index of refraction of 1.75. What is the critical angle for this material?

Sin(critical angle)=1/n, n being the index of refraction
how would i set up the formula? (critical angle)= Sin(n) ?? I am so confused

and

The critical angle for cubic zirconium is 29.2º. What is the index of refraction?

so...Sin(29.2º)= 1/n?...

my answer for this question is 2.049, rounded to 2.05

thank you,

mark
In the following discussion, sin-1 is the Inverse Sine function.
SOLUTION HINTS:
a) sin(θcrit) = (1/n) :: ⇒ :: θcrit = sin-1(1/n) = sin-1{1/(1.75)} = (34.85 deg)
b) sin(29.2 deg) = 1/n :: ⇒ :: n = 1/{sin(29.2 deg)] = (2.05)


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Last edited:
mark9159 said:
im having trouble setting my TI-83 Plus into "degree mode"

Press [MODE] and cursor down and right to the word Degree and hit [ENTER]
 
thank you very much
 
hahahhahah. are you in the BYU online homeschool thing too?
 
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