i recently read an article which said if you take the focal length divided by the Aperture stops, it would be how wide open the aperture is.
eg. focal length 100mm divided by Aperture f/10 means the opening is 10mm wide.
so at the same time, if focal length is 200mm, divided also by Aperture f/10, the opening will be 20mm wide.
does this affects the exposure in any ways? i've done practical tests but couldn't find any differences