How do I calculate the minimum internal pressure required to raise the lid of the pressure cooker, given weight of the lid, cross sectional area?
From my thoughts... Find the radius of the steam hole using some instrument like verniers.... Determine the mass of the weighted block... Pressure = (Force)/(Area) Here the force is the gravitational force ... i.e Mass x acc. due to gravity Area is the area of cross section of your steam hole... this will give you some value in Pascal units.....divide this value by 101325 to give the reading in atm unit.
Note all readings of weight must be in kilogram and radius in meters while calculating....
Im not sure external ambient pressure is to be taken in account for