In a U-tube there is some water and on top of the water in one of the tubes there is oil (water and oil don't mix). Find the density of the oil. (Hint: What can you say about the pressure at points a and b?)
Height of oil at point a on left-hand side of tube - 27.2 cm (the only part containing oil)
Height of water on corresponding right-hand side - 9.41 cm.