Becquerel was convinced at first that his hypothesis was supported which x rays would pass through the paper and leave an image. In addition, Becquerel original hypothesis is the uranium slat that gives off x rays when exposed to sun. Becquerel discovered by accident that uranium produces a type of radiation. The observation that caused Becquerel to pose another question is the same images was produces when the set up was left in a drawer and not exposed to sunlight.