# Exploring Light: Refraction & Wavelength Questions

• patriots1049
In summary, the properties of light such as refraction and index of refraction play a significant role in determining factors such as the speed and wavelength of light in different mediums. The index of refraction can be calculated using the speed of light in a vacuum and the speed of light in a specific medium. Snell's Law can also be used to determine the angle of refraction when light enters a new medium.
patriots1049

## Homework Statement

1. What property of light causes the sunlight to reach the Earth before the sun actually appears over the horizon?

2. What is the wavelength, in water, of blue light whose wavelength is 4.5 x 10^2 nm in air?

3.The speed of a certain liquid in a certain liquid is 3/4 the speed in a vacuum. What is the index of refraction of the liquid?

4. A clear plastic material has an index of refraction of 1.9. Light of frequency 4.5 x 10^14 Hz enters the plastic. What is the wavelength of the light while it is in the plastic?

5. A ray of light enters a piece of glass, making an angle of 50.0 degrees with the surface. What angle does the refracted ray make with the surface?

6. What is the index of refraction of a type of plastic for which the critical angle is 40.0 degrees.

## Homework Equations

Our teacher gave us this, with no information.

## The Attempt at a Solution

I need some formulas or a step in the right direction.

Anyway someone could walk me through some of these problems?

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You are required to put in some effort here. I don't see what you are even stuck on.

https://www.physicsforums.com/showpost.php?p=1042781&postcount=2

1. I think number 1 has to deal with the electromagnetic waves being refracted.

2. I know I do 3.0 x 10^8 * .700 to get the speed of light in water. Then I'm stuck.

3. The speed is 2.25 x 10^8, but I don't know how to get the index of refraction.

4. I am really lost.

5. 50 degrees as well?

6. Is it 1.54? sin(40) = .64 1/1.54 = .64

1. Photons, EM waves ... sounds ok.

2. If the wave is moving slower, what happens to the wavelength? You know how much slower, so what frequency do you get as a result?

3. What is the index of refraction? Have you looked it up?
http://en.wikipedia.org/wiki/Refractive_index#Definitions

4. Same method as 2.

5. See the Snell's Law link I posted earlier.

6. Yes. Close enough to 1.56.

## 1. What is refraction?

Refraction is the bending of light as it passes through different mediums, such as air, water, or glass. This bending occurs due to the change in speed of light as it moves from one medium to another.

## 2. How does refraction affect the appearance of objects?

Refraction can cause objects to appear distorted or even invisible when viewed through certain mediums. For example, when looking at a pencil in a glass of water, the pencil may appear broken or bent due to the refraction of light.

## 3. What is the relationship between wavelength and refraction?

The wavelength of light determines the amount of refraction that occurs. Shorter wavelengths, such as blue light, are more easily bent than longer wavelengths, such as red light.

## 4. How does refraction play a role in the formation of rainbows?

Refraction plays a crucial role in the formation of rainbows. When sunlight passes through raindrops, the different wavelengths of light are refracted at different angles, causing the separation of colors and the appearance of a rainbow.

## 5. Can refraction be controlled or manipulated?

Yes, refraction can be controlled and manipulated through the use of lenses, prisms, and other optical instruments. This allows for the creation of devices such as glasses, telescopes, and microscopes that rely on the principles of refraction to function.

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