1. The problem statement, all variables and given/known data An airtight box has a removable (massless) lid of area 4·10-2 m2. A lid is placed on it while it is on top of a mountain (where Patm=0.81·105 Pa). It is then taken to sea level, where Patm = 1.013·105 Pa. How much force will be required to remove the lid? 2. Relevant equations F=PA 3. The attempt at a solution For the first part: F=PA=.04 x 81000=3240 N For the second part: F=PA= .04 x 101200=4052 N is there a change in pressure type of equation?