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Science project idea on the relation of light to our ability to see things.
Light and Ability to See- Science Project Idea
How objects are visible.Our common experiences prove to us without further experiment that light must be present in order to see objects.Recall ex- periences which prove this.It is easy to understand how an object which produces light is visible, but how are objects like books, chairs, etc., visible?When light strikes an object, a book for example, some or all of the rays of light are reflected. If the surface of the book were perfectly smooth, the rays would all be reflected in the same direction, and no rays would reach our eyes unless we were in a certain location.The cover of the book, however, is not so smooth as it appears to be, and consequently the light rays striking these inequalities are reflected in every direction in straight lines, so that rays will reach our eyes regardless of our position, providing there is nothing between us and the object to intercept the rays. The effect of the inequalities may be understood by throwing several tennis balls together upon an irregular surface and noting the directions in which they bounce.The rays of light which pass into the eye from an object form an image or picture on the sensitive inner coat of the eye, the retina, just as such an image or picture is formed on the sensitive plate or film of a camera.In some way which we do not thoroughly understand, nerve fibers carry to the brain information of impressions made by the light on the nerve endings, and we become conscious of the size, color, and shape of the object.
How do you account for the fact that a room may be light although the sun does not shine directly into it?
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