Your eyes need to bend light rays so the image can be focused sharply on your retina. The better your retina records the image, the more likely that your brain will interpret the image, and the more likely you will see the image clearly. If a person has vision trouble, glasses or contact lenses are use. They bend the light rays in a way that lets you see more clearly.
1. State true or false :
Bifocals use a convex lens to bend light to make things look bigger.
a. TRUE
b. FALSE
2. Why does the light rays bend when a glass or contact lens are used for the person who is having vision trouble?
a. Due to reflection
b. Due to refraction
3. Light from the sun falling on a convex lens will converge at a point called
a. Centre of curvature
b. Focus
c. Radius of curvature
d. Optical centre
4. Power of convex lens is_____ and concave lens is ______.
a. Positive, positive
b. Positive, negative
c. Negative, positive
d. Negative, negative
5. The image formed by a convex lens can be
a. Virtual and magnified
b. Virtual and diminished
c. Virtual and of same size
d. Virtual image is not formed
