Lenses

Question 1

What is a converging (convex) lens?

Answer 1

A converging lens that causes parallel incident light rays to converge to a point after being refracted (thickest in the middle).

Question 2

What is a diverging (concave) lens?

Answer 2

A lens that causes parallel incident light rays to diverge after refraction (thinnest in the middle).

Question 3

What images do converging lenses produce?

Answer 3

inverted, real images that get larger as the object moves closer to F’

upright, virtual images that are larger when the object is inside F’

Question 4

What images do diverging lenses always produce?

Answer 4

upright, larger, virtual images when the object is anywhere in front of the lens.

Question 5

How do you draw light diagrams for converging lenses?

Answer 5

Parallel to optical centre - through F

Through optical centre

Question 6

How do you draw light diagrams for diverging mirrors?

Answer 6

Parallel - line up with F
through optical centre
(Trace backwards to a point)