Mass effects on the Terminal Velocity of a Coffee Filter Falling in Air
Written By: Ima Cool Performed with: Notso Lame
Question: How does increasing the mass of a coffee filter falling through air affect the
terminal velocity it reaches?
The mass of the falling coffee filter, independent variable, will be varied by nesting one
to four filters instead the initial filter. The terminal velocity, dependent variable, will be
read from a velocity-time graph generated from the motion sensor. The shape and
surface area of the filter will be controlled. In addition, all trials will take place from the
same height and within the same medium, air.
Materials: 5 coffee filters
electronic balance (±0.1 g)
computer with Data Studio & motion sensor
30 cm ruler (±0.05cm)
meter stick (±0.5cm)
Figure 1: Set-up of Materials used for data collection
1) Materials were set-up according to Figure 1. Within Data Studio, the motion sensor
was connected and a graphical display of velocity vs time was set-up.
3) Air temperature in the room was measured and recorded with the thermometer. The
air temperature was monitored throughout the data collection for any variations. Using
the electronic balance the mass of each coffee filter was measured. The diameter across
the opening of each coffee filter was measured using the 30 cm ruler.
4) Using the 30cm ruler, a single coffee filter was held 20.0 cm from the motion sensor.
The velocity-time graph was generated and the terminal velocity was recorded. This
process was repeated to generate a total of 3 trials.
5) Step 4 was repeated for 2, 3, 4 and 5 filters, nested inside one another (to maintain
surface area and shape of the filter) to generate the data set in Table 1.
Note: Any trial in which the filter `floated` out of the path of the beam was discarded.
Table 1: Several trials of the terminal velocity reached by varying masses of coffee filter
as they fall through air
Mass of Coffee
* The coffee filters were dropped from 2 meters above the floor, the air temperature of
the room stayed at 22.2±0.5
C, the surface area of the filter increased slightly over the
trials (diameter from 14.1±0.5 cm to 14.9±0.5 cm) and the mass of each coffee filter was
To determine the average velocity for the 1.1 g filter:
Ave terminal velocity =
Table 2: Average Terminal Velocity of Falling Coffee Filters in Air versus The Mass of the Coffee Filter
Mass of Coffee
Figure 2: Terminal Velocity vs Mass of Coffee Filter...