Course:PHYS341/Archive/2016wTerm2/Assignments/A9

Practice Questions for Quiz 9, Friday Mar 31

Textbook sections covered: (19.11-19.12), (20.1-20.10)

The three multiple-choice questions here have ONE answer.

1. The human voice is based on acoustical principles most similar to those involved in which type of instrument?

(a) bowed string instruments
(b) struck string instruments
(c) plucked string instruments
(d) air-reed woodwind
(e) cane reed woodwind (? a case could be made...)
(f) brasswind ✓

2. The human vocal tract behaves approximately as a

(a) cylindrical bore, closed at one end
(b) cylindrical bore, open at both ends
(c) conical bore, closed at one end
(d) conical bore, open at both ends
(e) complex and variable bore, closed at one end ✓
(f) complex and variable bore, open at both ends

3. The acoustic modes of the human vocal tract are very broad in frequency because of the soft nature of the walls of the vocal tract. Because of this, the modes are called formants, and can be shifted in frequency by altering the bore shape of the vocal tract. The frequencies of the first two formants are responsible for defining vowel sounds.

Use only the following words to fill in the blanks to form the most correct and precise sentence (words may be used more than once):
amplitude, consonants; formants, frequency; frequencies; hard; length; resonances, bore shape; soft; vowel

4. The sounds of all percussion instruments have what in common:
(a) short attack ✓
(b) long sustain
(c) short decay
(d) long decay
(e) indefinite pitch
(f) definite pitch