PASCO Xplorer GLX, Руководство пользователя

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138 B e a t F r e q u e n c y
Data Collection
1. Press and to turn on the Left and Right Output Channels.
Describe what you hear.
2. In the chart on the next page, write the frequencies of the Left and Right
Output Channels ( f
left
and f
right
).
You will use the GLX’s Stopwatch screen to time the beat period. Since it is not
practical to measure the very short time between two beats, you will time 10 full
beat cycles and later divide by 10 to calculate the period. Start timing on beat
“zero” and stop timing on beat “ten,” as illustrated below.
3. Press to return to the Home Screen; use the arrow keys to highlight
Stopwatch and press .
4. Count the beats, “zero, one, two, three, …, ten.” Press on beat “zero”
to start timing. Press again on beat “ten” to stop timing.
5. Write the elapsed time of 10 cycles in the chart below.
6. Press to reset the Stopwatch.
7. Press to return to the Home Screen; use the arrow keys to highlight Out-
put and press .
8. Use the arrow keys to highlight the Frequency of the Left Output Channel.
9. Press twice to increase the Frequency by 0.2 Hz.
10. Record the Frequencies of the Left and Right Output Channels in the next
line of the chart.
11. Repeat steps 3 through 10 until you have written data in 6 lines of the chart.
F1 F3
“one” “zero” “two”
“four” “three” “five” “seven” “six” “eight” “ten” “nine”
Audible
Sound
Level
Count:
beat period
10 beat cycles
F1
F1
F2
+