1. The problem statement, all variables and given/known data Problem statement: We are measuring the flow rates of liquids of different viscosities through holes of varying sizes. We ultimately want to observe the relationship between the viscosity and the flow rate, and also between the diameter and the flow rate. Variables: Independent- different liquids (different viscosities); diameter of hole Dependent- flow rate 2. Relevant equations Flow rate = ΔV/Δt 3. The attempt at a solution We need for all of our variables to be of quantitative nature but at the moment, we cannot measure the viscosity of our liquids. My main question is if I should try to graph the density of my liquids against the flow rate as opposed to the viscosity (since the density is something I can easily measure)? I am worried that this approach will lead to data upon which no conclusion can be drawn since the density of a liquid does not determine its viscosity. Basically I am hoping that there is an equation I can use that uses the flow rate and density of a liquid to calculate its viscosity. Is there such an equation?