You fill a balloon with helium and let it go. It floats up into the air, where it is essentially floating in a pool of air. Why does the helium filled balloon float in air? Make sure you use the words ‘buoyancy’, ‘density’ and ‘volume of displaced ‘air’ in answering this question.

Question 7 of 18 You come across an open container that is filled with two liquids. Since the two liquids have different densities, there is a distinct separation between them. Water, which has a density of pw = 1.00 × 10³ kg/m³, fills the lower portion of the container to a depth of 0.200 m. The fluid that is floating on top of the water is 0.307 m deep. If the absolute pressure on the bottom of the container is 1.049 × 10° Pa, what is the density, pi, of the unknown fluid? The acceleration due to gravity is g = 9.81 m/s² and atmospheric pressure is Po = 1.013 x 10° Pa. Pi = kg/m3

Consider a 3.9 kg freshwater fish whose tissues have an average density of 1050 kg/m^3. Part A To what volume in mL must the swim bladder be inflated for the fish to be neutrally buoyant at the surface? Part B What volume of air would have to be added to the swim bladder for the fish to remain neutrally buoyant at a depth of 20 m?

A stick of butter has dimensions 130 mm × 30 mm × 30 mm and density pt = 870 kg/m³. It is placed in a bowl of cool water and floats with its long side oriented horizontally. What volume of butter is submerged? (As always, drawing a force diagram is a great first step.) What is the smallest amount of mass m you must place on top so that the butter becomes fully submerged? Suppose that the stick is balanced very delicately so that it floats with its long side oriented vertically. How would this change your answers above?