I have two images below. This is a single piston with pressure inside, the variables are as listed. P_in = 2700 Pa. P_out = 0 Pa. R1 = Radius 1 = 10 cm. R2 = Radius 2 = 5 mm. P_contact = ? My solution to P_contact is as follows. Area A1 of piston at R1 = .0314m^2 and area A2 at R2 = 7.85x10^-5 m^2. The force exerted by P_in on the face of the piston with A1 is 84.78 N. Therefore P_contact = 84.78/ A2 = 1080000 Pa. I'm just wondering if this is correct? My second picture has a dual piston setup and my question is whether the P_contact variable on either side is halved?