For the our investigation let's pick air for the top substance and water for the bottom substance. Show the protractor. Take a random shot with the laser and then move the protractor so that it is centered where the beam enters the water. Remember the angle of incidence, reflection or refraction is the angle between the beam and with the perpendicular line to the surface (the vertical line). The protractor is setup to give you that angle when you use it.

A) Air and Water: Adjusting angle of incidence. wow For the our investigation let's pick air for the top substance and water for the bottom substance. Show the protractor. Take a random shot with the laser and then move the protractor so that it is center or refraction is the angle between the beam and with the perpendicular line to the surface (the vertical line). The protractor is setup to give you that angle when you use it. Be sure that the top substance is air and the bottom substance is water. For the experiment, take ten (10) readings starting at about 0 and then about every 10 until you reach 80 and record them in TABLE 1. Measure your angles (including the one you set your laser at, Top Substance Bottom Substance Take your laser beam shots from the upper left quadrant. See pic. Record the top and bottom substance types and index of refractions for each in the table. For each shot collect the incident angle, the reflected angle and the refracted angle. Make sure you report these angles relative to the perpendicular to the surface... the dotted line on the protractor. Use Snell's Law to calculate the refracted angle from the index of refraction of the top substance, the incident angle and the refracted angle. Report that calculated index of refraction in the table below. Snell's Law: nisin a = nzsing Table 1 Substance =Index Refraction Top Air 1.0003 Bottom Water 1.33 Calculated Index of Angle of Incident Refraction of Bottom Measurements (degrees) Reflected Angle, a Refracted Angle, B substance, n1 2 3 5 6 8 9 Q1. Average Index of Refraction: Q2. % Difference between Average Index of refraction and listed Index of Refraction of Bottom substance used