Question

What is long-sightedness? List two causes for development of long-sightedness. Describe with a ray diagram, how this defect may be corrected by using spectacles.
OR
What is an astronomical telescope? Draw a labelled ray diagram showing the formation of image of a distant object by an astronomical telescope. State the magnication produced by a telescope in normal adjustment. How can the magnication power of a telescope be increased?

Answer 1

I know this question answered

Answer 2

The medical name for long-sight is hypermetropia, sometimes called hyperopia. Eyesight problems, such as hypermetropia, are also known as refractive errors. Long sight leads to problems with near vision and the eyes may commonly become tired. Distance vision (long sight) is, in the beginning, good. Long sight can be corrected by glasses or contact lenses, or sometimes 'cured' with laser eye surgery.