Light- critical angle/refraction/reflection

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In summary, the conversation discusses three questions related to light and refraction. The first question involves finding the critical angle for light traveling from a liquid back into air. The second question involves finding the angle between reflected and refracted light when a ray of light strikes a block of clear ice. The third question involves using the index of refraction of water to find the height of a building when a laser beam is shone from a submarine to the surface of the water. The summary does not include any output before this information.
  • #1
physicsluv
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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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  • #2
I figured out 1 and 3, can someone help me with number two though?
 
  • #3
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:
 

1. What is the critical angle of light?

The critical angle of light is the angle at which a light ray traveling through one medium is refracted at a boundary with another medium, and the refracted ray makes an angle of 90 degrees with the normal to the surface. This angle is dependent on the indices of refraction of the two mediums.

2. How is light refracted at different angles?

Light is refracted at different angles because different materials have different indices of refraction, which influence the speed of light in that material. When light travels from one medium to another, it changes speed and is bent or refracted.

3. What is the relationship between critical angle and total internal reflection?

The critical angle is the angle at which total internal reflection occurs. If the angle of incidence is greater than the critical angle, the light is completely reflected back into the original medium. This phenomenon is known as total internal reflection.

4. How does the angle of incidence affect the angle of refraction?

The angle of incidence and the angle of refraction are related by Snell's Law, which states that the ratio of the sines of the two angles is equal to the ratio of the indices of refraction of the two mediums. As the angle of incidence increases, the angle of refraction also increases.

5. Why does light reflect off of shiny surfaces?

Light reflects off of shiny surfaces because of the principle of reflection, which states that the angle of incidence is equal to the angle of reflection. Shiny surfaces, such as mirrors, have a smooth and polished surface that allows for a more organized reflection of light rays.

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