Computer Intensive Physics Robert G. Fuller

One of the nice things about the coffee filter is that you can stack filters inside of one another and they look exactly the same to the air but, of course the mass goes up two, three, four, times as much. You can increase the gravitational force on the coffee filter while keeping the air resistance essentially the same (See Figure 36).

Portugal Conference

March 6, 199821 University of Nebraska - Lincoln

Another way to collect the same information is by using the computer-based real time physics software. In the United States PASCO sells "Science Workshop". But there are several examples of others available in Portugal. It has a little motion sensor. Here is a graduate student holding the coffee filter above the motion sensor (See Figure 37). You can drop the coffee filter and use the motion detector to measure the displacement. You get curves that look like this (See Figure 38).

Figure 37

21