1. The problem statement, all variables and given/known data A Partially evacuated airtight container has a tight-fitting lid of surface area 77m^2 and negligible mass. If the force required to remove the lid is 480N and the atmospheric pressure is 1x10^5 Pa, what is the air pressure inside the container? 2. Relevant equations p=F/A 3. The attempt at a solution p=F/A p=480N/77m^2 p=6.23Pa This did not make sense to me, so i thought maybe it was the difference in pressures: Po-Pd=Pf 1x10^5-6.23Pa=99993.78Pa?? I don't think that is right either. Where I am going wrong?