*This is not a homework question - I'm taking the iB and need to understand how liquid properties affects certain variables of a cylinder for my Extended Essay.
So basically, here's the scenario: There's a cylinder that's rolling down a ramp with a known liquid of known viscosity inside it.
I want to know how changing the viscosity of the liquid will affect the angular speed and resultant force and therefore the translational speed of the cylinder at the end of the ramp.
In my experiment, I used a PVC pipe of radius 10cm and inside it is half filled with water. Moreover, I vary the viscosity by adding corn syrup to the water and finding the viscosity using this method: http://www.wikihow.com/Measure-Viscosity
Moreover, I changed the volume of the liquid inside for each viscosity. I found a positive linear relationship between volume and translational speed. As volume increases, speed increases. I also do not understand why this happens. I've attempted to explain it using moment of inertia and conservation of energy but it didn't work because all the mass is cancelled in the equation. I'm guessing it's due to slosh dynamics but I can't seem to find much information on it.
TL;DR I want to know how liquid viscosity and liquid volume affects speed.