A robotic benthic explorer is floating on the surface of a highly saline lake and is stationary.
Add two labelled arrows to the diagram to show the vertical forces acting on the explorer.
The explorer then dives to perform a geological survey. It descends to a depth of 75 m below the surface.
State the equation linking pressure difference, depth (height), density and ggg.
The density of the saline water is 1200 kg/m3. Show that the pressure difference from the surface is 900 kPa when the explorer is at a depth of 75 m (use g=10 N/kgg = 10\text{ N/kg}g=10 N/kg).
A small pocket of air is trapped inside an open exterior compartment of the explorer as it dives.
Air at the surface has a pressure of 100 kPa.
Calculate the total pressure of the trapped air at a depth of 75 m below the surface.
The volume of the trapped air is 12.5 m3 when the explorer is at the surface of the lake.
Calculate the volume of the trapped air at a depth of 75 m below the surface, assuming the temperature of the air remains constant.
