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Bend a light beam through a water stream.

What You Need

  1. a strong flashlight
  2. an empty soda can

What You Do

  1. Take the empty soda can and have an adult poke a hole in the side of the can near the bottom with a strong sharp pencil.
  2. Ask your adult to make sure any sharp edges at the hole are pushed into the can so it’s safe for you to put your finger on the hole.
  3. Fill the can with water, holding your finger over the hole. Turn out the overhead lights and stand over a sink.
  4. Put a flashlight over the top of the can, and take your finger off the hole.
  5. Where the water stream lands, you’ll see a beam of light.

What's Happening?

The light from the flashlight bends and follows the water out of the hole in the can. The inside of the can and the surface of the water stream act like mirrors to reflect the beam of light. The light bounces around inside the water, and follows it wherever it flows.

Bill Nye