Density and Pressure

Explain, using the example of the Magdeburg hemispheres, how air pressure acts in all directions and what happens when the air is removed from inside the hemispheres.

Some people think that atmospheric pressure only acts downwards. Give two reasons, based on everyday or laboratory evidence, that show atmospheric pressure acts equally in all directions.

A laboratory set of Magdeburg hemispheres has a surface area of 0.060 m². The atmospheric pressure is 100,000 Pa.

Describe why a submarine must be designed with a strong hull when it dives deep in the ocean, with reference to liquid pressure acting at points on its surface.

A diver is swimming at a depth of m below the surface of freshwater. The density of freshwater is . The gravitational field strength is .

A tank is filled with oil to a depth of m. The density of the oil is . Take gravitational field strength as .

Calculate the pressure difference between the top and the bottom of the tank.

Explain why the pressure at the bottom of a swimming pool is greater than at the surface. Refer to molecules and the pressure-depth relationship.

Which change would double the pressure difference between two points in a liquid?

A student measures the depth and pressure difference in a tank of an unknown liquid. The table shows her results. Calculate the density of the liquid.

Take .

Describe an experiment to show that the pressure in a liquid increases with depth. Your answer should include the apparatus needed and how you would take measurements to show the pattern.