A circular hatch of radius 0.30 m separates two compartments of a research submarine. The air pressure in the forward compartment is 1.25×105Pa, while the pressure in the aft compartment is 9.0×104Pa. The hatch is mounted so that its plane is vertical and perpendicular to the line connecting the centers of the two compartments.
(a) Calculate the magnitude of the net force exerted on the hatch by the air in the two compartments.
(b) Determine the minimum constant force a crew member must apply, and specify its direction, to hold the hatch closed against the pressure difference.
(c) If the crew member instead pulls with a force of 1.0×104N opposite to the direction found in part (b), state whether the hatch will move, and justify your answer with appropriate reasoning.