Thin Lenses Experiment Essay

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Theory: The purpose of this experiment was to demonstrate and better understand thin lenses. The two types of thin lenses are concave where the lens curves in and convex when the lens curves out. There are three characteristics of thin lenses, which include; a chef ray, which goes through the center of the lens and does not deviate, the parallel ray that shines parallel to the lens and is refracted through the focal point on the opposite side, lastly there is the focal ray, which shines through the focal point that is on the same side of the lens as the object and at the middle of the lens is refracted parallel to the lens. At the point where two or more reflections of the rays meet is where the image is created. A real image is one that is …show more content…

Equations:

1/do + 1/di = 1/ 1/distance from object + 1/distance from image = 1/focal length

M = -di/do magnification factor = - distance form object/distance from image

1/f = (n-1) [1/R1 + …show more content…

The only thing that changes at every distance is the size. At 55cm the image was reduced, at 36cm the object stayed the same size, and at 30cm the object was enlarged. At 10cm the image became virtual as seen by the negative image distance, which means it is also upright, the size is enlarged even more than at 30cm going form a magnification factor of -1.6 to 2.25. Therefore, the image increases in size, as the object gets closer to the lens.
All concave lenses, will make a virtual image, regardless of their distance from the object. The images will also always be upright and reduced. This is due to the fact that it is not possible for any of the rays to cross on the other side of the lens because the rays diverge or spread apart once they ass through it.
As the object is brought closer to a concave lens it always remains virtual and upright. The image distance seems to decrease slightly with the objects distance. As the object gets closer to the lens the image does get larger but always remains smaller that its actual size.
Convex lenses are able to produce both virtual and real images. The virtual image occurs when the object is very close to the lens, 10cm or less. Concave lenses can only produce virtual images because the rays cannot converge on the other

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