Drop Time
- Measure the drop time of a small plastic ball (or any object
that isn't so heavy that it damages the force plate upon impact).
- The Pasco force probe is located 1 or 2 meters above the
floor, suspended by a ring stand, oriented with the force sensor pointing
down. A small plastic ball is pressed lightly up against the sensor and then
released. The ball lands on the force plate, resting
on the floor, directly beneath the force probe. The event is graphed using
logger pro, (in the picture above, the top graph is that of the force probe,
and the bottom the force plate) and one can determine the release time and
landing time by analyzing the graph. Time measurements are only accurate to
.02 seconds.
- Force probe and labpro device is located in L35, section
B2. Force plate is located in L02 section B3.
- Note: You might think that a photogate would
be the more effective and convenient way to measure the release time. But
for some reason, when the photogate is used drop times are consistently measured
to be .04 seconds too short. Which amounts to about 10% error.