# How Does the Index of Refraction Change Across Different Materials?

• tigert2004
In summary, the conversation discusses using Snell's law to determine the index of refraction of material 1 and material 2. The incident angle and refraction angle are given for material 1, and the index of refraction is calculated to be 1.79. However, this may not be correct due to potential confusion with the angles. The conversation suggests trying a different point on the graph to get a more accurate answer.
tigert2004
In Figure 33-48a, a light ray in a liquid (n = 1.61) is incident at angle 1 on a boundary with an underlying material, into which some of the light refracts. There are two choices of underlying material. For each, the angle of refraction 2 versus the incident angle 1 is given in Figure 33-48b. Without calculation, note whether the indices of refraction of material 1 and material 2 are greater or less than the index of the liquid.

What is the index of refraction of material 1?

What is the index of refraction of material 2?

I understand that you use snells law,
and
Material #1:
Incident Angle = 67.5 deg
Refraction Angle = 56.25 deg
→ n1 = nwater*Sin(Incid Ang)/Sin(Refr Ang)
= (1.61)*Sin(67.5 deg)/Sin(56.25 deg)
= 1.79

which isn't correct

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The picture is still pending approval... but my gut instinct is that you may have your angles mixed up. The angle stays with the index of the material that ray is in:

$$n_{air}\sin{\theta_{air}}=n_{water}\sin{\theta_{water}}$$

tigert2004 said:
In Figure 33-48a, a light ray in a liquid (n = 1.61) is incident at angle 1 on a boundary with an underlying material, into which some of the light refracts. There are two choices of underlying material. For each, the angle of refraction 2 versus the incident angle 1 is given in Figure 33-48b. Without calculation, note whether the indices of refraction of material 1 and material 2 are greater or less than the index of the liquid.

What is the index of refraction of material 1?

What is the index of refraction of material 2?

I understand that you use snells law,
and
Material #1:
Incident Angle = 67.5 deg
Refraction Angle = 56.25 deg
→ n1 = nwater*Sin(Incid Ang)/Sin(Refr Ang)
= (1.61)*Sin(67.5 deg)/Sin(56.25 deg)
= 1.79

which isn't correct
Try using a different point on the graph where the curve intersects the grid points on the right edge. It will make some difference in your answer.

## 1. What is reflection and refraction?

Reflection and refraction are two principles of light that describe how light behaves when it interacts with different materials. Reflection occurs when light bounces off a surface, while refraction occurs when light passes through a material and changes direction.

## 2. What causes reflection and refraction?

Reflection is caused by the interaction between light and a surface. When light hits a surface, some of it is absorbed, some is transmitted, and some is reflected. Refraction is caused by the change in speed and direction of light as it passes through a material with a different density.

## 3. How are reflection and refraction used in everyday life?

Reflection and refraction are used in a variety of everyday objects and activities. Mirrors, glasses, and lenses all use reflection and refraction to manipulate light. They are also used in photography, telescopes, and microscopes to capture and magnify images.

## 4. What is the difference between reflection and refraction?

The main difference between reflection and refraction is the direction of light. Reflection occurs when light bounces off a surface at the same angle it hits it, while refraction occurs when light bends as it passes through a material with a different density.

## 5. How do scientists study reflection and refraction?

Scientists study reflection and refraction using various experiments and mathematical equations. They also use tools such as lasers, prisms, and lenses to manipulate and measure light. Additionally, computer simulations can be used to model and understand the behavior of light in different materials.

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