1 of 17

To describe how lenses work

Science - Light and Sound

2 of 17

Activity 1: Draw a biconvex lens with 5 light rays passing through. In your diagram, include a principal axis, focal point and a focal length.

2

3 of 17

Activity 2: Draw a thicker biconvex lens with five light rays passing through next to your diagram from activity 1. Predict how light rays will travel.

3

4 of 17

Activity 3: Compare the thinner and thicker biconvex lenses. Describe differences and justify your answer.

4

5 of 17

Activity 4: Draw a biconcave lens with five light rays passing through. In your diagram, include a principal axis, focal point and a focal length.

5

6 of 17

Activity 5: Draw another diagram, where an appropriate corrective lens (concave) is used to correct the vision.

6

Myopia (Short-sightedness)

7 of 17

Activity 6: Draw another diagram, where an appropriate corrective lens (convex) is used to correct the vision.

7

Hyperopia

(Long-sightedness)

8 of 17

Activity 7:

Maria noticed that whenever she tried to read a book, words were too blurry to see. She could still see distant objects without any problem.

Suggest an eye condition that Maria may have and recommend a corrective lens to support her vision problem.

8

9 of 17

9

Answers

10 of 17

Activity 1

10

Convex Lens

Focal point

Principal axis

Focal length

11 of 17

Activity 2

11

12 of 17

Activity 3

12

Answer: Focal length is shorter in thicker biconvex lens. This is because light rays are refracted much more in the thicker biconvex lens.

13 of 17

Activity 4

13

Image credit: Oak National Academy

Focal point

14 of 17

Activity 5

14

Image credit: pixabay

Myopia (Short-sightedness)

Concave lenses help diverge the light, so that the focal point is formed on the retina

Myopia with correction

15 of 17

Activity 6

15

Image credit: pixabay

Hyperopia

(Long-sightedness)

Convex lenses help converge the light, so that the focal point is formed on the retina

Hyperopia with correction

16 of 17

Activity 7:

Maria may have hyperopia, which is an eye condition, where focal point is formed behind the retina. This is suggested because she is having problems with objects up-close, but can see distant objects well.

She is recommended to wear a convex lens to support her vision, which will help the focal point to be formed at the retina, as the convex lens converges the light.

16

17 of 17

17

Developed in partnership and made possible �by joint funding from Commonwealth, state �and territory governments.

For more resources

edresearch.edu.au

ochre.org.au

@EdResearchAU

@OchreEducation