Procedure: wave speed and frequency, Question, Procedure: wave speed and water depth – PASCO WA-9899 Ripple Tank System User Manual
Page 28
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R i p p l e T a n k S y s t e m
E x p e r i m e n t 6 : W a v e S p e e d
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Procedure: Wave Speed and Frequency
1.
Turn on the ripple generator and the light source. Set the light source to
‘STROBE’. Set the frequency to 5 Hz and the amplitude slightly less than half of
maximum. Adjust the amplitude if needed to make a clear wave pattern.
2.
The waves fronts appear as light and dark stripes that are formed as light travels
through wave crests and troughs. Measure and record the distance of five wave-
lengths.
3.
Choose a new frequency and repeat the measurement of the distance for five
wavelengths. Do this for five different frequencies.
4.
Calculate the wavelength that corresponds to each different frequency.
5.
Based on the wavelength and frequency, calculate the wave speeds.
6.
Calculate the average wave speed.
Question
1.
Is the wave speed roughly constant for the frequencies you chose?
Procedure: Wave Speed and Water Depth
1.
Set the ripple generator frequency to 5 Hz. Measure and record the distance of
five wavelengths as in the previous procedure.
2.
Drain or add water so the depth is 7 mm. Adjust the ripple generator so the plane
wave dipper is barely in contact with the surface of the water. Measure and
record the distance of five wavelengths as before.
3.
Repeat the procedure for depths of 5 mm and 2 mm.
4.
Calculate the wavelength and wave speed for each water depth.
Question
1.
How does the speed of the wave depend on the depth of the water?
Table 6.1:
Frequency (Hz)
5 Hz
Five
λ
(m)
λ
(m)
v (m/s)
Table 6.2:
Depth of Water (mm)
Five
λ
(m)
λ
(m)
Wave Speed (m/s)
10
7
5
2