PASCO ME-6664 Photogate Tape Set - Manual (Page 6)

Model No. ME-6664 Photogate Tape Set
5 ®
A velocity reading is taken from leading edge-to-leading edge on a
section of the tape (Figure 1a).
One velocity reading is recorded for every 5 cm (.050 meters) band
(black and white pair) of tape that moves through the photogate beam.
The velocity is calculated from the
distance/ time or 0.050 m/
time of each band. The number of data points equals the total number
of 5 cm bands (minus 1) that travel through the beam of the photogate.
For example, if the tape moves 5 meters through the photogate bracket,
this equates to 50 bands, and you could expect approximately 100 [or
100-1= 99] individual velocity readings or data points on a graph.
However, if the Photogate beam is positioned over the middle of the
black section at the start of the timing, the photogate beam skips that
section and begins the timing at the first leading edge of the next
consecutive black section.
In the example below (Figure 1b), one velocity data point is taken (V
1
,
V
2
, V
3
, V
4
, etc.) for each band on the tape, giving a total of 4 points/20
cm. These data points can be viewed or averaged in a DataStudio
display.
leading
edge
leading
edge
band 1 band 2 band 3
leading
edge
leading
edge
Figure 1a: Bands on Photogate Tape
∆ ∆ ∆
Figure 1b: Strip of Photogate Tape
V
1
V
2
V
3
V
4
5 cm 10 cm 15 cm 20 cm