Bending the Light

Materials:

• Plastic Bottle

• Laser Beam

• Knife or Nail

• Water

• Tape

• Paper Towel Roll

Safety Regulations:

-Be careful when using the knife or nail to cut a whole in the bottle

Procedure:

1. Cut a hole in the water bottle and tape it.

2. Cut a hole in the paper roll at the same height as the hole in the bottle so that the beam of light can go through the hole

3. Fill the bottle with water and cap the bottle tightly to avoid water spilling

4. Align the light beam in the paper roll with the bottle

5. Adjust the laser so that is kept on

6. Turn all lights off

7. Uncap the bottle and take the tape off to let the water run

8. The stream of water will trap the beam of light and bend as the water flows

Scientific Principle:

When light hits the boundary between 2 substances it often bends or refracts. Total Internal Reflection is a phenomenon that can occur when a beam of light passes from a denser medium into a less dense medium. Critical Angle is formed when the angle of the refracted light does not enter the rarer medium but instead travels along the surface between both medians and can be found by knowing the refracting indexes of the 2 materials. When light crosses into new medium some of the water will refract and some will reflect and the angle formed from refraction is given by Snell's Law. Law of Reflection states that the light waves can pass from one medium to another and this will change the direction of the light making it to bend which is caused by a change in the speed of light as it travels through different mediums. The light and the water both come out hole horizontally and as the water curves down the light hits the surface, and since the angle between the surface and light is slight the light bounces off.