I know that pins prevent horizontal and vertical translation and that rollers prevent only the vertical one. Therefore, what I do not understand here is that while the support at B reacts with two forces C support has only one, even though both look like pins to me.Where am I going wrong here?
(I could not find anything on the site about whether I can upload images this way. I hope there are no copyright issues related to my post because I do not own the images. If there is, please notify me and I will immediately take them.)