The Power of a Magnifying Glass Essay Example for Free

The Power of a Magnifying Glass EssayThe magnification of a magnifying glass depends upon where it is placed between the users eye and the object being viewed, and the total distance between them. The magnifying advocatorfulness is equivalent to angular magnification (this should non be confused with optical office staff, which is a different quantity). The magnifying world power is the ratio of the sizes of the images formed on the users retina with and without the lens.3 For the without contingency, it is typically assumed that the user would bring the object as cobblers last to the eye as possible without it becoming blurry. This point, known as the near point, varies with age. In a teenage child it can be as close as 5 cm, while in an senior(a) person it may be as far as angiotensin-converting enzyme or two metres. Magnifiers are typically characterized using a standard value of 0.25 m.The highest magnifying power is obtained by putting the lens in truth close to th e eye and moving the eye and the lens together to obtain the best focus. The object lead whence typically also be close to the lens. The magnifying power obtained in this condition is MP0 = + 1, where is the optical power in dioptres, and the factor of comes from the assumed distance to the near point ( m from the eye). This value of the magnifying power is the one normally used to characterize magnifiers. It is typically denoted m, where m = MP0. This is sometimes called the total power of the magnifier (again, not to be confused with optical power).Magnifiers are not always used as described above, however. It is more more comfortable to put the magnifier close to the object (one focal duration away). The eye can then be a larger distance away, and a good image can be obtained genuinely easily the focus is not very sensitive to the eyes exact position. The magnifying power in this case is roughly MP = . A typical magnifying glass might have a focal length of 25 cm, correspo nding to an optical power of 4 dioptres. Such a magnifier would be sold as a 2 magnifier. In actual use, an observer with typical eyes would obtain a magnifying power between 1 and 2, depending on where lens is held. Using this principle, a magnifying glass can also be used to focus light, such as to concentrate the suns radiation to create a hot pick out at the focus.