1-2 Explaining how we see things with the eye (1.1)

• Natuurkunde
• Middelbare school
• havo
• Leerjaar 2

How do we see colour

(p. 14)

Bluetooth 

- On

Stationary

- Books

- Pen and pencil

- iPad

Report

- NO

Lessonup

- Yes

Bags in

the cuboard

Phones in the phone holder

Lesson goals:

• Explain how the eye can see.
• How do the colours of a tv work.
• A coloured object under 

      a coloured lamp
       ... what happens?

Jigspace - the eye

1. Work in groups of two
   
2. Install the app - jigspace
   
3. Look for the eye
   
4. Complete the worksheet 
   

Time: 12 minutes

And then? Then we will discuss it

We will still use jigspace 3 more times, so dont delete it

Compatibility:

- iPhone 6 or later

- iPad 6th generation

- iPad pro

How does the eye work?

• You see colours with light-sensitive cells in your eyes. 
  
• These cells are called cone cells. 
  
• There are seperate cones 

       to observe green, blue and 
       red light. 

• Cones can also see 

       neighbouring colours in the spectrum

Colours of the tv

• A tv only uses three colours, 

       red, green and blue lines.

• So for yellow the tv sends our green and red light.
• A good example is a

       'living colours' -lamp

Under a coloured lamp

• A sodium lamp emits orange light.
• A blue car under an orange lamp appears black, because a blue car can only 

     reflect blue light

A colour tv only works with red, yellow and blue pixels.

1. True
2. False

With only three colours, you can make all the colours of the rainbow.

1. True
2. False

Under a coloured lamp it is possible for objects of colour to appear black.

1. True
2. False

Most colour blind people can not distinguish between red and green.

1. True
2. False

Which colors are NOT observed by the cones?

1. Red
2. Yellow
3. Blue
4. None

Which cones react more strongly to the light of a candle?

1. Red and blue
2. Red and green
3. Green and blue

Why do you not see colour when observing things in the moonlight.

1. Rods dont see colours
2. Cones dont see colours
3. There is no colour present

Which colour is absorbed by a red surface?

1. Red
2. Blue
3. Yellow
4. Green

Do the following questions:

11, 12, 14 (p. 15)

In your writingbook

Rules: 

- 5 minutes

- No talking

Finished early: Research on the web how tv's work

In a nutshell:

• Eyes have rods and cones by which we observe colours. 
• A tv only emits green, blue and red light. Through a combination of these colours, other colours are observed.
• Under a coloured lamp, 

       colours may appear different