In my interview they asked me one question on geograpy: if russia was a neighbour of Pakistan. I had trouble digesting the simplicity of it. I dont think they go into details for geography, general knowledge should do.
A lot of interview questions depends on the mood of interviewers, your number for interview that day, the performance of the candidate who've been interviewed before you and so on.
physical geogprahy is about facts and if you can draw neat diagrams thats an added bonus, i dont think it should make a very big difference if u didnt place equator running exactly through northern brazil...but i hope you didnt draw the line through southern argentina