Question

A long, clear, flexible tube is bent into a U shape(open at both ends), and we pour water into it (density 1000 kg/m3)until the water reaches the same level on both vertical sides. Now we pour a 7 cm column of mercury into the left side(density 13,600 kg/m3), which does not mix with the water. (a)When the fluids reach equilibrium, find the difference in elevation between the top of the mercury (on the left) and the top of the water (on the right). Which Is higher? (Hint: Any two points at the same elevation, connected by a single continuous liquid, must be at the same pressure.) (b) Find the difference in elevations if the liquids are reversed, i.e., if the tube is first filled with mercury, then 7 cm of water is poured in at the left end. Which end is higher in this case?

Answer 1