A review sheet asking for definitions of about 12 factors dealing with light was used to start the class and review work from last week. A second sheet of problems dealing with angles of incidence and angles of reflection was was also completed at the start of the class. A set up of a plane piece glass, with a burning candle on the right side and a burning candle on the left side was used as a demonstration to determine the relationship between object distance and height and image distance and height. The object candle was moved until the image of the candle reflected from the glass overlapped exactly the burning candle on the right of the glass. The distance of the object candle was measured in cm and the image candle measured in cm. The distances from the mirror were found to be equal, as was the height of both candles and flames. When looking into a plane mirror, the image appears to be in the mirror at the same distance as the object is in front. As the object moves closer or farther away, the image moves the same distance. Di = Do. A printed ray diagram was used to show how the image is formed by a plane mirror, the rays of light were labeled as well as the distances from the mirror.