Lenses

Question 0

diverging lens

Answer 0

a lens that is thinnest in the middle and that causes incident parallel light rays to spread apart after refraction

Question 1

converging lens

Answer 1

a lens that is thickest in the middle and that causes incident parallel light rays to converge through a single point after refraction

Question 2

optical centre

Answer 2

point at the exact centre of the lens

Question 3

principal focus

Answer 3

the point on the principal axis of a lens where light rays parallel to the principal axis converge after refraction

Question 4

emergent ray

Answer 4

the light ray that leaves a lens after refraction

Question 5

accomodation

Answer 5

the changing of shape of the eye lens by eye muscles to allow a sharply focused image to form on the retina

Question 6

hyperopia

Answer 6

the inability of the eye to focus light from near objects; far-sightedness

Question 7

positive meniscus

Answer 7

a modified form of the converging lens shape

Question 8

presbyopia

Answer 8

a form of far-sightedness caused by a loss of accommodation as a person ages

Question 9

myopia

Answer 9

the inability of the eye to focus light from distant objects; near-sightedness

Question 10

negative meniscus

Answer 10

a modified form of the diverging lens shape