Mystery #2Tier 2-3materials / light
Why can you see straight through solid glass but not through a solid wall?
You can stand at a window and watch the whole garden, yet the glass in front of you is a solid you cannot push your hand through. A brick wall is solid too, but you cannot see a thing through it. Both are hard and solid. So why does light sail straight through one and not the other?
Your guess
What do you think happens to the light when it reaches the glass?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
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