Light- critical angle/refraction/reflection

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The discussion revolves around solving problems related to light refraction and reflection. The user is struggling with three specific questions involving critical angles and the relationship between incident and refracted light. For the second question, the user has calculated the refracted angle but is unsure how to determine the reflected angle, prompting a request for clarification on the relationship between these angles. The conversation highlights the importance of understanding Snell's Law and the principles of reflection in optics. Overall, the user seeks assistance in solidifying their grasp of these concepts.
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I am stuck on three questions :(
Formulas: nsin(x)=n sin (x)
sinx=n2/n11. A ray of light traveling in air strikes the surface of a liquid. If the angle of incidence is 26.0◦ and the angle of refraction is 19.3◦, find the critical angle for light traveling from the liquid back into the air.
This is my work so far:
1sin(26)=xsin(19.3)
x=1.326

sinx=1.326/1
I then get an error. I do not know what I'm doing wrong :(

2. A ray of light traveling in air strikes the surface of a block of clear ice (n = 1.309) at an
angle of 58.4◦ with the normal. Part of the light is reflected and part is refracted. Find the angle between the reflected and the refracted light.
Work so far:
1sin(58.4)=1.309sinx
x=40.59213054
I believe that this is the refracted angle, but what is the reflected angle/how do I find it?


3. A submarine is 316 m horizontally out from the shore and 120 m beneath the surface of
the water. A laser beam is sent from the submarine so that it strikes the surface of the
water at a point 223 m m from the shore. If the beam strikes the top of a building
standing directly at the water’s edge, find the height of the building. The index of refraction of water is 1.333.
Answer in units of m
Work so far: None, because I can't even comprehend it.
Thanks for your help in advance :)
 
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I figured out 1 and 3, can someone help me with number two though?
 
physicsluv said:
I figured out 1 and 3, can someone help me with number two though?

Great! :approve:

So for (2),

physicsluv said:
2. A ray of light traveling in air strikes the surface of a block of clear ice (n = 1.309) at an
angle of 58.4◦ with the normal. Part of the light is reflected and part is refracted. Find the angle between the reflected and the refracted light.
Work so far:
1sin(58.4)=1.309sinx
x=40.59213054
I believe that this is the refracted angle, but what is the reflected angle/how do I find it?

What is the relation between angle of incidence and reflection for any plain mirror? :wink:
 
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TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
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