Why does glass cast a shadow, and whay determines the depth of color of the shadow cast?

Question

One day I noticed that a piece of glass in my house did not cast a visible (to me) shadow, but my glasses did. I was wondering why.

Answer 1

Shadows form as a result of blocked light pathway. In term of glass, this depend on the thickness and how opaque the glass is, the thicker and foggier, the more light gets blocked and hence shadow. Different material and surface may influence as well. (i.e glasses refracts light due to uneven surface, therefore more light gets blocked

Answer 2

Normal window pane glass is fairly straight and does not change the angle of the rays after they pass through the glass. The light may change direction when it enters the glass, but it will change back to the original angle when it exits the other side. Therefore, no effect to the light that you see coming through it.

Your glasses on the other hand are either convex or concave in nature, with the distinct requirement that light will be affected as it travels through the lenses. Since the light changes, even if just a little bit, the area beneath the glasses will have a different level of illumination than beside it. We will see that as a shadow.

Answer 3

During day light, the sun directs countless photons in a straight line. Anything that blocks or diverts the sun's rays of photons will create a shadow. A window pane will block or reflect only a small amount of light and its shadow is hard to distinguish. Your eye glasses focus the light even though they block or reflect only a little light. This may create a partial shadow or even concentrated light depending on whether you are near or far sighted. The depth of color of a dark shadow may result from the fact that less colored light reaches your eye and you must see more with the rods on your eye's retina than from the cones.

Answer 4

Well this is depending on the thickness and clarity of the glass if its a real clear glass and pretty thin it most likely won't show a shadow but a more thicker piece of glass such as a window used for basements would most likely cast some sort of shadow..that's my best guess..