waves

final day lalive tbh

pitch

perception of the frequency of a sound wave

loudness

determined by amplitude of sound wave

where do strings (in SHM) have the most tension?

at the lowest point

(Ke is the highest)

open end pipes

1. ends of harmonics are antinodes

2. nodes = n

3. antinode = n+1

4. wavelength = 2L/n

5. frequency = nv/2L

closed end pipes

• begins with node

• nodes = antinodes = n

• wavelength = 4L/n

  • n is odd

• frequency = nv/4L

possible harmonics

• open end pipes - any number

• closed end pipes - odd numbers

fundamental frequency

n =1 (first harmonic)

relationship with overtones: fn = f1 * n

doppler effect

Frequency of sound (pitch) heard by the observer is higher when the observer and source get closer. When observer and source are farther, frequency gets lower

beat frequency

number of "beats" heard per second

fb = f2-f1

beat

two waves completely in phase

standing wave

• stationary

• remains in constant position

wave sources

• amplitude

• frequency

• type of waves (transversal or longitudinal)

• DO NOT affect speed

wave medium

• density

• tension

• affect speed

traverse wave

disturbance and coil move perpendicular to each other; moves side to side

longitudinal wave

disturbance and coils move parallel to each other

constructive interference

when two pulses meet and they have an amplitude in the same direction → bigger wave

destructive interference

when two pulses meet and they have amplitudes in opposite directions → smaller wave

node (N)

location of minimum/no vibration

antinode (A)

location of max vibration