Course:PHYS341/Archive/2016wTerm2/Assignments/A5

Practice Questions for Quiz 5, Friday Mar 03

Textbook sections covered: 14.2-14.4, 14.7

1. Which ratio(s) of frequencies form the backbone of every musical scale across the globe?

(a) The equal temperament semitone, 1.05946:1
(b) The equal temperament tone, i.e. two semitones
(c) The major third 5:4
(d) The perfect fourth 4:3 ✓ (arguably)
(e) The perfect fifth 3:2 ✓ (arguably)
(f) The octave, 2:1 ✓ (definitely)

2. In the Pythagorean system, a fifth above A4 (440 Hz) is E5 (660 Hz). What is the frequency of a note that is a fifth above A♭2 (100 Hz)?

(a) 101.5 Hz
(b) 150 Hz ✓
(c) 200 Hz
(d) 225 Hz
(e) 320 Hz

3. In the Pythagorean system, what is the frequency of a note that is two fifths above A♭2 (100 Hz)?

(a) 103 Hz
(b) 150 Hz
(c) 200 Hz
(d) 225 Hz ✓
(e) 320 Hz

4. For an equal temperament scale, circle the true statement(s) below?

(a) All intervals have exact small-integer ratios
(b) Intervals of a third (minor and major), a fourth and a fifth are close to but not exactly small-integer ratios ✓
(c) The octave intervals are exactly 2:1 ✓
(d) The octave intervals are close to but not exactly 2:1
(e) All pairs of notes a semitone apart have the same frequency difference
(f) All pairs of notes a semitone apart have the same frequency ratio ✓

5. Why was the equal temperament scale introduced around 1600?

(a) Because it became mathematically possible then ✓
(b) Because fret-less string instruments like the violin needed a standard to work to
(c) Because string instruments and wind instruments needed the same standard
(d) To allow keyboard instruments to play music in different keys ✓
(e) To allow fretted instruments to play music in different keys ✓