Physics Grade 11

Unit 4: Waves and Sound

Note 6: Music and Factors Affecting Frequency


Reference: Chapter 10.2. 10.4


 Briefly summarize the wave characteristics (i.e. amplitude, frequency, harmonics) that describe music: pitch, loudness, quality

Music: sound with one or more constant frequencies. The more harmonics the better quality of music.

Noise: sound with randomly changing frequencies

Pure Tone: only one frequency (i.e. Tuning fork)

Note: Low frequency (low pitch means long wavelength) and high frequency (high pitch) means short wavelength.

Designing for Acoustics of a Room:


Curved versus Flat rooms
Outdoor - curved so performer is at focal point so people can hear them.
Indoor - flat since curved would focus noise in one spot indoors.

With stringed musical instruments the string is fixed at both ends (node at each end).

Four factors affect the frequency of vibration of a string: Do proportionalities.

    1) length       2) tension     3) diameter of the string      4) density of the string


Lab: Handout 'Calculating the Speed of Sound'

- lab will be done in groups but individual reports are required.

Pg. 460 #1,4,8,9,10Pg . 463 #3,4