In case of some crystals such as calcite, when light is passed through two rays come out giving rise to two images. One is found to be stationary and the other one is moving around the first as we...
The word 'ordinary' has multiple senses: 1: (heraldry) any of several conventional figures used on shields; 2: a judge of a probate court; 3: an early bicycle with a very large front wheel and...