What parameters are being tested in the three investigations?

What is the mathematical formula for density?

How does radius relate to density?

What is the definition of viscosity?

What is the name of the force that acts on an object slowly moving through a liquid?

Define terminal velocity. How can you determine terminal velocity from a velocity vs. time graph?

What do you expect to happen to terminal velocity as density increases? As viscosity increases? As radius increases?

In this experiment, you will be recording spheres as they fall through the liquid. You will use the manual tracking plugin in ImageJ to record the time, position, and velocity of the spheres in each frame of your video. Your goal is to determine the relationship between the terminal velocity and your parameter (radius, density, or viscosity). What type of graphs and/or charts should you use to complete your analysis and prove your hypothesis? Why?

You will use tweezers to drop the sphere into the liquid. It is very important to submerge the tweezers (with the sphere) into the liquid before releasing the sphere. Why do you think this step is important? (Think about what forces are present in the liquid vs. the air above the liquid)

Steel Sphere in 45% Glycerin 2500 2000 1500 velocity (cm/s) 1000 500 0 0.00 0.05 0.10 0.15 0.20 0.25 -500 time (s) Determine the terminal velocity from the velocity vs. time graph above