# Physics Experiments: Light and trapped inside the water stream

Another take at our light trapping experiment, this time using a red laser pointer. We punched a hole in the plastic bottle and filled the bottle with water. As the water flows through the hole, the trick is to point directly at the hole through the bottle. This makes the photons enter the water stream and they can no longer leave it, getting reflected inside the stream and traveling along with it, so no longer in a straight line. This is exactly the way fiber optic cable works.

Simon gave me a whole lecture the other day about how fiber optic cable transmits binary data like a morse code, with long light flashes for ones and short flashes for zeros. (“And underwater robots fix them!”) He explained ASCII, the way to encode English letters and special characters in binary, 95 characters in total: “7 bits allowing for 128 combinations, which is even an overkill. To transfer pixels, you need 24 bits. And 2 to the 24 is exactly the same as 256 to the third (total number of possible shades). I worked this out!”

With two bottles:

Physics

# Antibubbles

Simon having fun making antibubbles – bubbles that have water inside them instead of air. Learned this from a Physics Girl video and this online instruction: https://www.antibubble.org/page2.html

# How much iron is there in your favorite cereal?

If you put a cereal flake in a bowl of water you can steer it with a strong magnet. The magnets above aren’t strong enough, but the really powerful ones below (that are dangerous to pull apart as they can actually injure you) are:

And if you grind the cereal into powder, the powder sticks to the magnet because of the iron atoms in the cereal:

Inspired by the Veritasium channel.

# For Mom’s birthday

For my birthday, Simon made me some Fireworks:

He made them look even better the following day, by adding trails:

The code is Simon’s translation into Lua (the language of the Codea app) of Daniel Shiffman’s Fireworks Coding Chalenge (JavaScript).

We’ve also thoroughly enjoyed our birthday weekend at Brugge and especially Knokke. Fine to discover such fabulous beaches in the neighborhood. Simon loves water. Perhaps, because it is somehow related to the fluidity and of his mind and because of the freedom water provides to his body.