1. The problem statement, all variables and given/known data Determine the magnitude and direction of the effective value of g at a latitude of 45 degrees on the Earth. Assume the Earth is a rotating sphere. 2. Relevant equations a = v2/r 3. The attempt at a solution This question requires a vector diagram no doubt. What I know is that there is gravity force towards to center of the Earth and normal force exactly opposite to it, and also centripetal force along the x axis. But centripetal force here confuses me as I don't know how to draw it. In my early problems with circular uniform motion, centripetal force was always component of some other force -like normal force, tension force, or friction force. I don't recall drawing an Fcentripetal in the vector diagram for questions like these: But in this gravity question, I think I need to show that there is an Fcentripetal along the x axis? Or is it nothing more than a component of gravity force?