**Your
Answer to Q240.** Sorry, your answer is **not** correct. What determines
pitch?

Help: *Fundamentals of
Sound*, Sec. 7-D.

Or would you like a **HINT**?

You should try to work out
the answer on your own, but if you insist on reading it the correct answer is
**here** .

Return to Question 240.

**Hint
for Question 240:** Pitch is determined by repeat frequency. How do
you determine that?

Return to Question 240.

**Your
Answer to 240. **Congratulations, your answer is **correct**.

If you would like, you can compare your answer to the "official" correct answer .

Return to Question 240.

**Correct
Answer to Question 240:** Pitch is determined by repeat frequency. You
determine the repeat frequency *f* by the rule that *f* is the **largest
common factor of the frequencies in the spectrum**. In I this is just the
fundamental *f*_{0} = 100 Hz. In III and V, the repeat frequency
is again *f*_{0} even though that frequency is not actually in
the spectrum. However the frequencies that are present are multiples of *f*_{0},
and that is the largerst common factor. II contains harmonics that are all multiples
of 200 Hz so that is the repeat frequency. In the same way the repeat frequency
of VI is 200 Hz, since the sixth harmonic, 600 Hz is three times 200 Hz. In
IV, the repeat frequency is 300 Hz since the other frequency component, 600
Hz, is twice that.

Thus III and V have the
same repeat frequency as I . a) is correct.

Return to Question 240.

0

**Your
Answer to Q250.** Sorry, your answer is **not** correct. What
are the two features of this wave that makes it possible to distinguish among
the spectra?

Help: *Fundamentals of
Sound*, Sec. 7-B.

Or would you like a **HINT**?

You should try to work out
the answer on your own, but if you insist on reading it the correct answer is
**here** .

Return to Question 250.

**Hint
for Question 250:** Note that the wave is symmetric and that it has
four nodes. That information should allow you to determine the spectrum.

Return to Question 250.

**Your
Answer to 250. **Congratulations, your answer is **correct**.

If you would like, you can compare your answer to the "official" correct answer .

Return to Question 250.

**Correct
Answer to Question 250:** Because the wave is symmetric (that is, the
right part is the mirror image of the left) then the wave spectrum contains
only symmetric harmonics. These are the odd harmonics, *f*_{0},
3*f*_{0}, 5*f*_{0}, etc. This means that only c) and
d) qualify. However, because the wave has four nodes and looks a lot like the
third harmonic, we expect that the amplitude of this harmonic will dominate
the spectrum as in d) which is the correct answer.

Return to Question 250.

**Your
Answer to Q255.** Sorry, your answer is **not** correct. Use
the rule for finding the repeat frequency.

Help: *Fundamentals of
Sound*, Sec. 7-D.

Or would you like a **HINT**?

You should try to work out
the answer on your own, but if you insist on reading it the correct answer is
**here** .

Return to Question 255.

**Hint
for Question 255:** The repeat frequency is the largest common factor
of the frequencies in the spectrum.

Return to Question 255.

**Your
Answer to 255. **Congratulations, your answer is **correct**.

If you would like, you can compare your answer to the "official" correct answer .

Return to Question 255.

**Correct
Answer to Question 255:** The repeat frequency is the largest common
factor of the frequencies in the spectrum, which is 6 Hz. The repeat time is
the inverse of this or 1/6 s.

Return to Question 255.

**Your
Answer to Q260.** Sorry, your answer is **not** correct. How
do you determine the repeat frequency?

Help: *Fundamentals of
Sound*, Sec. 7-D.

Or would you like a **HINT**?

**here** .

Return to Question 260.

**Hint
for Question 260:** The repeat frequency is always the fundamental or
one of the higher harmonics, depending on the spectrum.

Return to Question 260.

**Your
Answer to 260. **Congratulations, your answer is **correct**.

If you would like, you can compare your answer to the "official" correct answer .

Return to Question 260.

**Correct
Answer to Question 260:** The repeat frequency is always the fundamental
or one of the higher harmonics, depending on the spectrum. The longest it could
be is the period of the fundamental. If one of the higher harmonics is the repeat
frequency than the repeat time is shorter. The statement is true.

Return to Question 260.

**Your Answer to Q270.** The correct answer is
15 Hz. If you did not get that correct, try again.

Help: *Fundamentals of
Sound*, Sec. 7-D.

Would you like a **HINT**?

Read the "official" correct
answer **here**.

Return to Question 270.

**Hint
for Question 270:** What is the rule for determining the repeat frequency?

Return to Question 270.

**Your
Answer to 270. **Congratulations, your answer is **correct**.

If you would like, you can compare your answer to the "official" correct answer

Return to Question 270.

**Correct
Answer to Question 270:** To determine the repeat frequency, you must
find the largest common factor of the frequencies present in the spectrum. These
frequencies are 30, 45, and 90 Hz. The largest common factor is 15 Hz. The frequencies
are respectively 2, 3, and 6 times 15 Hz. Thus the repeat frequency is 15 Hz.

Return to Question 270.

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