A. Refraction, reflection, and scattering. Place the laser near the center of the lab bench, pointed horizontally. Turn it on and wait a moment to see the red light. Hold an index card vertically and place it in the laser beam. This allows you to see where the beam goes. With a piece of paper under the beam place the bottom edge of the card on the paper, and intersect the beam with a vertical edge. Make a mark on the paper directly under the beam. Move the index card and make another mark, indicating the path of the beam. Place the empty plastic container in the path of the beam such that the light hits a side at an angle of incidence of about 30 (from perpendicular). Slide a piece of paper under the container. Trace around the container to show where it is on the paper. Carefully draw lines on the paper noting all the paths of the light leading to the container, reflected from the container, and transmitted through the container. Put little arrows on the lines to indicate what direction the light was traveling. Fill the container with water. Repeat the procedure carefully drawing lines on another paper representing all the paths of the light. You might want to place your finger in the water to see where light is going in the container. Don't forget to note the directions the light is traveling. Remove the container. Measure the angles of incidence, reflection, and refraction for the air filled container and for the water filled container. These angles are measured from a line perpendicular to the surface of the container. Is the law of reflection confirmed by your measurements? Is the law of reflection confirmed for the reflection within the water? From your data, and using Snell's Law, find the index of refraction of the water (assume the index of refraction of the air is 1.00). Put the full container on another piece of paper. Swish a bar of soap in the water once or twice to yield more scattering from the solution. Look at the scattering from above, from the side, and at a small angle from in front of the beam. Where do you need to be to see the highest scattered intensity? Look at the scattered light from above and from the side through a polarizer. Is the scattered light polarized? What direction is it polarized? Take your polarizer outside and look through it at the blue sky (don't look at the sun). Is the blue sky polarized? Why? Move the container so that the beam enters through the short side of the container. Can you change the angle of incidence so that the beam is totally internally reflected? Since this occurs only when going from higher index of refraction to lower, the internal reflection must be occurring at the glass-air interface. Adjust the angles and the soap density to see the largest number of reflected beams. How many reflected beams can you see in the solution? (Sketch your results.) Who can get the largest number of internal reflections