Day 94: Terminal Velocity II


Students in IS II used LoggerPro and the motion sensors to find the terminal velocity of falling coffee filters. Graphing was done on LoggerPro and lab reports were written on Google Drive and then submitted electronically for grading and commenting. Graphs were inserted into the report by “screen shooting” them. Students must also submit a self-scored copy of the lab grading rubric found on the class Moodle. Anyone who thinks education in 2014 is the same as it was when I was in high school (1975-1978) is nuts.

Day 89: Coffee Filters and Position-Time and Velocity-Time Graphs

Screen shot 2014-01-15 at 11.45.26 AM

I introduced terminal velocity yesterday. Most students had no idea what it was. They had a lot of misconceptions (penny off the Empire State Building will kill you). Today we had short periods so we had time for the Mythbusters Penny Drop video and a quick analysis of a distance-time graph and a velocity-time graph for a falling coffee filter. The graphs showed beautifully that the filter accelerated for less than a second (as seen by the curved d-t graph and the corresponding straight line on the v-t graph) before reaching a terminal velocity of about -0.55 m/s (shown by the straight line with (-) slope on the d-t graph and the horizontal line on the v-t graph). Tomorrow they do their own investigation with coffee filters.