In the previous part of this lesson, the use of ray diagrams were introduced and illustrated. Ray diagrams can be used to determine where a person must sight along a mirror in order to see an image of him/herself. As such, ray diagrams can be used to determine what portion of a plane mirror must be…
The line of sight principle suggests that in order to view an image of an object in a mirror, a person must sight along a line at the image of the object. When sighting along such a line, light from the object reflects off the mirror according to the law of reflection and travels to the person’s eye. This…
As discussed in the previous section of Lesson 2, an image location is the location in space where all the reflected light appears to diverge from. Since light from the object appears to diverge from this location, a person who sights along a line at this location will perceive a replica or likeness of the actual object. Virtual…
Why is an Image Formed? In Lesson 1 of this unit of the Physics Classroom Tutorial, the manner in which light reflected off objects in order to allow us to see them was discussed. A major principle in that lesson was expressed as follows: In order to view an object, you must sight along a line at…
It was mentioned earlier in this lesson that light reflects off surfaces in a very predictable manner – in accordance with the law of reflection. Once a normal to the surface at the point of incidence is drawn, the angle of incidence can then be determined. The light ray will then reflect in such a manner that the…
Light is known to behave in a very predictable manner. If a ray of light could be observed approaching and reflecting off of a flat mirror, then the behavior of the light as it reflects would follow a predictable lawknown as the law of reflection. The diagram below illustrates the law of reflection. In the diagram, the ray of light…
In the first section of Lesson 1, it was stated, “without light, there would be no sight.” Everything that can be seen is seen only when light from that object travels to our eyes. Whether it be a luminous object (that generates light of its own) or an illuminated object (that reflects the light that is…
Reflection and its Importance The Role of Light to Sight The bottom line is: without light, there would be no sight. The visual ability of humans and other animals is the result of the complex interaction of light, eyes and brain. We are able to see because light from an object can move through space…
As is often the case, physics is not a science that is restricted to the sterile confines of a laboratory. Physics is naturally and frequently seen by any observer who glances at the world around them. An informed physics student should see physics in action on a daily basis and should be able to exclaim without embarrassment…
The previous section of Lesson 3 discussed Thomas Young’s effort to derive an equation relating the wavelength of a light source to reliably measured distances associated with a two-point source light interference pattern. The equation, known as Young’s equation is: λ = y • d / (m • L) In 1801, Young devised and performed an…