Present Remotely

Send the link below via email or IM

• Invited audience members will follow you as you navigate and present
• People invited to a presentation do not need a Prezi account
• This link expires 10 minutes after you close the presentation

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

The Physics of Musical Instruments

The Sound basics, The Percussion, The Strings, and the Vocal/Wind/Brass
by

on 26 September 2012

Report abuse

Transcript of The Physics of Musical Instruments

The Physics of Musical Instruments By Bailey Borchers, Erin Horner, and Madeleine Wilmsen Percussion Vocal, Wind, and Brass Strings String Sounds Physics? In all stringed instruments, the strings are fixed at both ends, and are plucked, bowed, or strummed to produce a standing wave. The string vibrates against the air particles causing a sound wave. The velocity of a wave traveling in a vibrating string and the tension of that string is calculated by the following equation: The nodes or places of zero displacement on the wave are at the ends of the string. Since the nodes are at the end of the strings, the strings will also vibrate at other wavelengths that have nodes at the end. Formula for Instruments The equation for finding pitch in both woodwind and brass instruments is λ=2L/n, where n<=1. The L is the length of the pipe. The equation for a pipe closed at one end is λ=4L/(2n+1), where n<=0. Brass Instruments Brasses are sounded by the vibration of the player's lips when they are lightly pressed against a mouthpiece and the player blows between them. Vocal Sound We can sing because our glottis(The part of the larynx that contains the vocal cords and the space between them) is able to adopt a convergent (opening) and a divergent (closing) configuration alternating within a glottal cycle. By opening and closing the vocal cords, we are able to change pitch and sing. Woodwinds When the player blows air into the instrument through the reed, it causes a vibration to occur inside the instrument, and makes a sound depending on the keys held down and those open. A percussion instrument is any instrument that relies on vibrations of the instrument. This usually happens through banging or hitting of the instrument. For instruments with a definite pitch, you would use the equation:
f = 1.03kv/L2
For drums or other instruments with an indefinite pitch, you would use the equation:
f = (0.764/D)(F/)½ L= the length of the bar, V=the velocity of sound in the object, and k=constant but changes depending on the object Vibration and Resonance Resonance is when one object vibrates at the same frequency of a second object which then forces the second object into vibrational motion When all three types of instruments play together, the vibrations in the instruments create sound waves in the air which in turn create harmonies. Thanks for watching! Sound Basics How to measure a wave Physics? A sound wave is a mechanical longitudinal wave.
This means that the wave needs a median to travel through, such as air. The longitudinal part describes the motion of the wave. This means that the median and the wave are parallel. A wavelength is the shortest distance between two points before the motion is repeated. It is represented by "lambda." Sound waves use two points, one called a compression (the point of highest concentration of particles in the medium) and rarefactions (the points of the least amount of concentrations). Frequency= 1/T
By knowing the frequency of a wave and the wavelength of the wave, you can find out the speed or velocity. V=(lambda)xf Even if all of the instruments play at the same frequency, they will still sound different because they are made out of different materials. v = [ T / (m/L)]^½
T is the tension in Newtons
m is the mass of the string
L is the length of the string Fundamental Frequency:
Has a wavelength equal to 2 times the length of the string. Definite Pitch Examples:
Xylophone and Timpani
Indefinite Pitch Examples:
Snare drum and small "auxiliary percussion" like the Tambourine That sound like this... Physics? Physics?
Full transcript