Physical Science 20 - May 19

Today in Period 2, students wrote the quiz on Speed of Light, Magnification and Curved Mirrors.  After they finished, they had the rest of the class to work on Assignment 3.1 and Part B of the Refraction Practice Problems.  Students will hand in Assignment 3.1 and I will go over Part B tomorrow.  In Period 4, we moved on to look at critical angle and total internal reflection.  Critical angle is a special incident angle where the refracted angle will be 90 degrees.  If light tries to exit a substance at an angle greater than the critical angle, it wont be able to and it will just reflect around inside.  This is called total internal reflection.  They copied notes from slides 57-61 and worked on Part C of the Refraction Problems for the remainder of the class.  These will be due on Thursday.  Tomorrow we will start to look at optics and lenses.