# Light 2

The flashcards below were created by user Anonymous on FreezingBlue Flashcards.

1. What are the two types of lenses?
• Converging lens (Convex)
• Diverging lens (Concave)
2. What are converging lenses?
• They are convex lenses.
• They make parallel light rays converge/meet at a particular point.
• The lens is thick in the middle and thin at the ends.
3. What are diverging lenses?
• They are concave lenses.
• They make parallel light rays diverge after going through it.
• The lens is thin in the middle and thick at the ends.
4. Images formed by converging lenses
• As long as the object is outside the focal point, the image is real and inverted.
• When the object is inside the focal point, the image is virtual and upright.
• When the object is at 2F, the image formed is the same size as the object.
5. List down formulas to find Linear magnification, m

and

6. How are images formed in our eye?
• Light falling on object is reflected in all directions.
• Some reflected rays enter the eye.
• These light rays are bent (refracted) by the cornea, vitrous humor, lens, etc.
• Bent light rays meet on the retina.
• An inverted image is formed.
• Images on retina creates impulses, which will travel to the brain by sensory neurones.
• Brain interprets impulses so that the viewer sees the object right way up.
7. Name the two types of eye defects.
• Long-sight - can see far objects clearly, but near objects appear blur. (corrected by converging lens)
• Short-sight - can see near objects clearly, but far objects appear blur. (corrected by diverging lens)
8. Accommodation
• Changes of lens shape
• When I try to focus on a distant object, my lens become thin
• When I try to focus on a nearby object, my lens become fat
 Author: Anonymous ID: 167968 Card Set: Light 2 Updated: 2012-08-29 13:56:39 Tags: Physics Light Folders: Description: Lenses, application to eye, etc Show Answers: