Secondary Science- Light

From Eduwiki

By Sara Wilson

Misconceptions about Light

1. Student definition - Light is a form of energy and that is all

* Students usually create own definition.
* Spend time exploring properties, not defining.

2. Light is not an entity that exists in the space between the source and where the effect is produced (Mostly 10-11 year olds)

3. Light only leaves a source for a short distance

* Students draw light diagrams of a source with short rays extending from it.
* Often light diagrams use very few lines/rays that connect a source and the object studied.

4. Students' understanding of light is psychological not physical

* Student quotes: "The light is bad." 

5. Light is a wire or road going from point A to point B

6. Light travels further at night

* Students often think that light doesn't go very far from its source.
* 40% of students believe that light travels different distances at different times of day.

7. Shadow is an actual presence that light allows you to see (younger children)

* Shadow of an object is in the shape of the object.
* Older students realized it was an absence of light but still noticed the reproduction of form.

8. Light stays on a mirror during reflection

9. A lens needs to be whole to form an image

10. Light bounces off mirrors or not other objects

11. Light bounce off opaque object but doesn't effect what we see

12. Moving back from the mirror allows them to see more of themselves in a mirror

13. Refraction (Broken pencil in water misconceptions)

* Water made it look broken.
* Water bends the light rays.
* The shape of the beaker makes it look broken.
* Water is a magnifier

14. Red light filter on projector misconceptions

* White light is changed to red.
* White light projects the color of the filter.

15. Color is the property of an object

* Light helps us see the object.
* Our eyes see the color of the object not light.

Concepts Students Struggle With

1. The path light takes isn't visible

* Darkness important to their concepts of light.
* In diagrams students would shade in darkness instead of light.

2. Secondary Sources of Light

* Students could name many primary sources of light but no/few secondary sources.

Student Thinking

Types of responses received from students when questions about light are given.

1. Ambient Light - Direct light vs. Daylight (runs from bright to dark)

2. Composite Light - Describe the composition of light (single thing or many parts/bits)

3. De-coupled Light - Light separate from seeing

4. Illuminative Light - Light is designed (on purpose) for us to be able to see

5. Modal Light - There are different kinds of light with different effects

6. Obvious Light - Light is a property

7. Projected Light - Light is a substance that is projected (transports colors)

Students often think of light as something that is not scientific. (75% didn't pick scientific answer)