Coffee Lab - Drag Coefficient

Background: Drag coefficient can be defined as a resistance on an object such as air or water. Terminal velocity can be achieved when the drag coefficient and the gravity force are equal. As for the lab, when the coffee filter falls in such a short distance, the drag coefficient will get to be large enough that there would be a terminal velocity. Aft first however the force of gravity will be greater than the drag coefficient; thus meaning that the coffee filter is accelerating. While the filter is accelerating and the velocity is increasing so is the drag force.

Materials: The materials needed in this lab are 4 coffee filters, a stopwatch, electronic balance and a meter stick.

Procedure:

1. Determine a height, for where all the coffee trials will fall at

2. Find the mass of the coffee filter

3. Drop the coffee filter from your chosen height 5-10 times

4. Time from when the coffee filter is released to when it touches the ground

5. Record Data (make a chart of mass, height, time, and velocity)

6. Repeat steps 1-5, but instead stack 2 coffee filters together, then 3 coffee filters, and lastly 4 coffee filters

Essentially, the coffee filters, being light with relatively large surface areas exposed to the air, reach terminal velocity very quickly, so for all intent and purpose, you can assume in each case that the filter or filters move at constant speed throughout their fall, then explain this in your error analysis. So first calculate the speed in each case, then since the filters are moving at constant velocity, you can apply newton's __??___ law to each case and note that the air resistance must be equal to __???___________