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:

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s