6) A sub has a volume of 20 m3 and a density of 1500 kg/m3. It sinks to a depth of 40 meters. The density of sea water is 1025 kg/m3.
a. What is the pressure on the sub at this depth?
b. The sub has a window with a diameter of 30 cm. What is the net force on the window of the sub?
c. What is the buoyancy force on the sub?
d. State the magnitude and the direction of the force necessary to keep the sub at this depth.