Questions:
230.
Repeat time
232. Symmetry
233. Repeat time from symmetry
235. Repeat time
230. A standing complex wave on a string of length 4 ft is made by adding the fundamental, f0, and a fourth harmonic of frequency 4 Hz. What is the repeat time of this standing complex wave?
Fundamentals of Sound reference:Secs. 7-B, 7-D.
Check your answer HERE.
232. What is the symmetry of the complex wave shown on this string tied at both ends?
a)
symmetric
b) antisymmetric
c) mixed symmetry
Fundamentals of Sound
reference:Sec. 7-B.
233. What is the repeat time of the complex wave shown in Question 232?
a)
The period of the fundamental.
b) The period of the second harmonic.
c) The average of the periods of all the
harmonics used in making the wave.
d) One can't tell from the information given.
Fundamentals of Sound
reference:Secs. 7-B, 7-D.
235. Three complex sound waves are created by adding different frequencies in the harmonic series based on f0 = 10 Hz, that is 10 Hz, 20 Hz, 30 Hz, 40 Hz, etc. The three waves contain the following constituent frequencies:
Wave 1: 10 Hz and 20 Hz
Wave 2: 10 Hz, 20 Hz, and 40 Hz.
Wave 3: 10 Hz, 50 Hz, and 100 Hz.
a)
The repeat time of all 3 waves is the same
b) The repeat time of all three waves is
1/10 s
c) All three waves may have different
repeat times
d) The repeat time of the 3 waves depends
on the phases of the constituent frequencies, so we can't tell anything
about the repeat time
e) Both a) and b)
f) Both c) and d)
g) None of the above
Fundamentals of Sound
reference:Secs. 7-B, 7-D.