Light
 |
Student project |
|---|---|
 |
Introduction
Light is write this section last... [1]
What Is Light?
Light refers to the visible light portion within the electromagnetic spectrum. This visible light travels through electromagnetic fields in the form of energy packets called photons. A photon is an elementary particle that travels both as an electromagnetic wave and as a particle, and has properties of both. For example, light can be reflected and refracted just like waves, but can also strike and affect other particles like electrons. This property of light is called wave-particle duality.[3]
Properties Of Light
Light has many interesting properties that still fascinate physicists today.
Reflection
When light strikes a reflective surface, it will bounce off it at a different direction. The angle of the reflected beam is equal to the angle of the beam hitting the reflective surface, or, more simply stated by the Law of Reflection, “the angle of incidence is equal to the angle of reflection”. There are two types of reflection: specular and diffused. Specular reflection is reflection off of a flat surface, such as a mirror. This produces a flat, undisturbed picture. Diffused reflection is reflection coming off of a rough or bumpy surface, producing a muddled and unclear picture. [4]
Refraction
Whenever light travels through a boundary between two mediums, the light bends. This is because of the density differences between the two mediums. Since one of the mediums is more dense than the other, the speed of light within the medium is slower, and this causes the bending. This can be seen when items underwater such as fish appear larger while under the water than they are out of the water. [5]
Dispersion
The white light that we normally see is not really the color white. In actuality, it is a combination of all colors that makes the light appear to be white. If white light is shone through a prism or similar object, then the white light will disperse and separate out into all of the colors. A rainbow is an example of dispersion. After a rainstorm, many tiny water particles hang suspended in the air, and as white light hits the water droplets, they act like a prism, causing the white light to separate out into all of the colors.[5]
References
- ↑ Title Author, Publisher, Date.
- ↑ 2.0 2.1 Title Author, Publisher, Date.
- ↑ What is a Photon? Andrew Jones, About.com, Accessed April 10, 2011
- ↑ Reflection Think Quest, Accessed April 10, 2011
- ↑ 5.0 5.1 Properties Of Light Physics Planet, Accessed April 10, 2011
Additional Information
- Title Author, Publisher, Date.
