Day 112: Pinholes and Reflection

How do you know light travels in a line? We looked through camera obscuras and drew pictures to understand how the light makes the images we saw. Then we practiced a bit before we moved on to our first test of the ray model of light—reflection. We learned the three-pin method for finding a ray of light that goes through three pins, hitting the mirror at the second pin. We came up with a very simple law for reflection.