1. The problem statement, all variables and given/known data A person with a mass of 80kg pulls horizontally on the handle of a door which is locked. At that instant, the ground reaction force has a magnitude of 810N. What is the force applied to the door? (200 N) 2. Relevant equations 3. The attempt at a solution It seems like there is something missing in this question and does the persons mass really matter? I am really confused on this one.