Print and color this image from Sandlotscience.com to create a color-reversed illusion.

This unknown chalk pastel artist creates unbelievable 3-dimensional images on the sidewalks of the city.

Are the two red segments always the same size? Press the guide button to find out.

Do you see four concentric red squares? Use the green square to find out.

How many triangles do you see?

Observe the red and the green segment and predict if they are aligned.

Explore the world of central visual pathways. The visual pathway leads from the eye to the primary visual cortex. There is a detailed visual description of this process. Check it out.

Brief biography of Mohammad ibn Zakariya al-Razi, famous for his contributions to the fields and studies of medicine, astronomy, philosophy, and physics.

This site discusses primary lighting sources and gives information on the different properties and spectral characteristics of each. Also includes links to some interactive Java applets.

The moon appears bigger at the horizon just as it is rising over the treetops, than it does later in the evening when it is overhead. This is because our perception of its size changes based on where it is in the sky. In this human...

This article from Khan Academy provides information about mirrors. This information is intended for the Class 12 Physics Course (India).

Have you ever wondered why some people need glasses and others don't? It's because of the way light is focused by the lens in your eye. This lens, like magnifying glasses, eyeglasses, and contact lenses, is considered a thin lens.

A sound biography, focusing mainly on Bragg's science, what he discovered and what it's significance was. Lists many of his honors.

The concept of colors is discussed on this page. Read about primary colors, how complementary colors are created, what the process of color subtraction is, pigments and dyes, plus more. Also included are interactive Java tutorials.

Have you ever thought about your shadow? One way to learn about them is to make your own shadow box theater--once a very popular form of entertainment in Europe during the 1800s and early 1900s.

This interactive computer microscope Java tutorial explores how the hardware (QX3 microscope) and computer software work together to produce digital images.

The law of reflection is discussed and explained, accompanied by an animation depicting this law. Includes a list of links to detailed information about certain types of reflections.

Scroll down to Lesson 2 for a tutorial on image formation in plane mirrors. The tutorial from Glenbrook South High School provides lessons on why and how an image is formed, image characteristics for plane mirrors, ray diagrams, plus more.

This site from The Florida State University provides an informational page on electromagnetic radiation discusses the characteristics and properties of its many forms including X-rays, gamma rays, ultraviolet radiation, infrared...

Ray diagrams are useful tools for determining the location of an image as produced by a concave mirror. All concave and convex mirror ray diagrams can be constructed from knowledge of the behavior of two rays. Learn here about ray diagrams.

Ray diagrams are useful tools for determining the location of an image as produced by a concave mirror. Of all the rays which emanate from the top of the object arrow and are incident to the mirror, there are two rays whose behavior at...

Ray diagrams are useful tools for determining the location of an image as produced by a concave mirror. Of all the rays which emanate from the top of the object arrow and are incident to the mirror, there are two rays whose behavior at...

This animation depicts the path of light to each person's eye. Different people are sighting in different directions; yet each person is sighting at the same image location. In this animation the image location is the intersection point...

A reference page that explores how an image is formed in a concave mirror. Page includes a ray diagram that shows the geometrical lines of sight.