How we see things (grade 5)

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Transcript of How we see things (grade 5)

HOW WE SEE THINGS

Grade 5

How do we see? Which part of

your body are used to see?

The Brain

The eye

How do we see an object?

Light will be reflected in the same direction if it hit Polish,

Smooth, shiny and flat surfaces

Reflection on the mirror

Mirror

Normal

Incid

ent

Ray

Reflecte

d Ray

Reflection : Light bouncing back from a

surface

Experiment result about reflection on mirror

Scattered :reflection of rays in random direction

Light hitting rough surfaces like wood, stone, paper, or wool will bounce off them in all directions (scattered)

Testing Reflective Materials

Pale colour reflects more light than dark one. And mirror is the best material to reflect most light because it

smooth and shiny

Following are some rooms with different wall colour

The more pale the colour the more it reflects light

PERISCOPE

Steps to make a periscope

3. Draw the reflection ray of following picture

40

Mirror

4. Draw the reflection ray of following picture

40

Mirror

40

4. Draw the reflection ray of following picture

40

Wood

5. Which object applies reflection?

The other objects are applying refraction

Take a straw then insert it into a glass of water

Draw the image of straw and glass from the side of the glass then tell the changes

Take a clear plastic sheet. Drop a drop of water on to the plastic using a straw. Put the drop of water over a printed text!

Draw the image of printed text under the drop of water then tell the changes!

What happen to the light when it enters different medium?

The light is bent