الأسبوع 10 · المحور 2، الباب 1 «ماذا في سماء الليل؟» (ب): القريب والبعيد والتلسكوب وقصة كوكبة · 3 دروس
1
Near, far, bright and faint
Discover P2 Term 1: Axis 2, Chapter 1
GoalExplain that things far away look smaller and fainter, and test it with a torch.
New words
near · a short way from usfar · a long way from usbright · giving a lot of lightdim · giving only a little light
Explanation
Look at a tree close to you. It looks tall. Now look at a tree of the same size far down the road. It looks small. The tree did not shrink! It only looks smaller because it is far away. Light is the same. A torch close to a paper makes a bright spot. When the torch is moved far away, the spot is dim. Stars are very big, but they are so far away that they look small and faint.
Worked examples
Two buses are the same size. The bus far down the road looks small. When it comes near, it looks big.
Torch
Light on the paper
very close
brightest
an arm’s length away
dimmer
a table’s length away
even dimmer
Farida shines a torch on a paper. When the torch is very close, the light is brightest. When she moves it back, the light gets dimmer. When she moves it even farther, the light is even dimmer.
Marwan holds up his hand and looks at his friend across the playground. The friend looks as small as a finger. When Marwan walks up to him, the friend is taller than his hand!
Class activity
Near and far test with a grown-up. Put a toy on a table. Stand next to it, then walk ten big steps back. Hold up your hand and look at the toy. How big does it look next to your hand? Walk back to it. Is the toy really small? Then, in a dim room, shine a torch on a paper from very close, from an arm’s length, and from farther away. Say: bright, dimmer, even dimmer. Never shine a torch in anyone’s eyes.
Practice
1
A car is far away down the road. Does it look big or small?
Small. It only looks small because it is far away.
2
A torch is moved far away from a paper. Is the light on the paper brighter or dimmer?
Dimmer.
3
These two flowerpots are really the same size. Which one is nearer to us? Say the letter.
