3Phy Musical Instruments

Front 1

amplitude

Back 1

the maximum distance a wave moves from its central position

Front 2

antinode

Back 2

the point on a standing wave where the medium has maximum vibration

Front 3

crest

Back 3

highest point on a transverse wave

Front 4

frequency

Back 4

the number of wavelengths that pass a point in one second

Front 5

Hertz

Back 5

the unit for measuring frequency

Front 6

period

Back 6

the time taken for one complete wave to pass a point

Front 7

transverse

Back 7

a wave whose vibrations are perpendicular (at right angles) to its direction of travel

Front 8

wavefront

Back 8

waves travels out from a source in circles called wavefront. Wavefronts are lines at right angles to the direction of the wave.

Front 9

wavelength

Back 9

he distance between any two corresponding positions on a waves e.g. crest to crest, trough to trough, compression to compression.

Front 10

standwaves

Back 10

A vibration of a system in which some particular points remain fixed while others between them vibrate with the maximum amplitude.

Front 11

superposition

Back 11

adding the displacement of one wave to another.

Front 12

in phase

Back 12

when the points on two waves have the same motion. When two waves are exactly in phase (also known as 0degress phase difference) they add to give double the amplitude.

Front 13

out of phase

Back 13

when the points on two waves have the opposite motion. When two waves are exactly out of phase (also known as 180degress phase difference) they add to give zero displacement.

Front 14

phenomenon

Back 14

a situation that is observed (something that we see or can measure)

Front 15

mechanical wave

Back 15

vibrations passing through a solid, liquid or gas.

Front 16

medium

Back 16

a material (that mechanical waves travel through)

Front 17

electromagnetic wave

Back 17

waves made up of an electric and magnetic field (do not need a medium to travel through). e.g. radiowaves

Front 18

longitudinal

Back 18

a wave whose vibrations are back and forth in the same direction it is travelling.

Front 19

propagation

Back 19

movement of the wave, the direction in which a wave travels.pulse - a small section of a wave (i.e. not a continuous wave).

Front 20

trough

Back 20

lowest point on a transverse wave.

Front 21

compression

Back 21

points on a longitudinal wave where particles are closer together (higher pressure in a gas).

Front 22

rarefaction

Back 22

points on a longitudinal wave where particles are further apart (lower pressure in a gas).

Front 23

wave velocity

Back 23

the velocity at which a point on the waves travels e.g. how fast the crest of a wave moves through water.

Front 24

pulse

Back 24

a small section of a wave

Front 25

source

Back 25

object that emits (gives off) waves

Front 26

incident

Back 26

an incoming wave that hits something such as end of a string.

Front 27

reflected

Back 27

an outgoing wave the rebounds from something such as the end of a string.

Front 28

boundary

Back 28

the point between two different mediums

Front 29

pitch

Back 29

how high or low a musical note is due to its frequency, e.g. high frequency = high pitch.

Front 30

intensity

Back 30

how loud a sound is due to its amplitude e.g. high amplitude = high intensity.

Front 31

timbre

Back 31

the characteristic sound that different musical instruments give to the same notes. Due to different waveforms but the same frequency, also seen on the frequency graph where they have the same fundamental frequency but different harmonic frequencies at different levels.

Front 32

constructive

Back 32

when the displacement of two waves add to make a larger displacement.

Front 33

destructive

Back 33

when the displacement of two waves add to make a smaller displacement (or cancel out to give no displacement).

Front 34

node

Back 34

the point on a standing wave where the medium is not vibrating.

Front 35

harmonic

Back 35

the frequencies of vibration that will cause standing waves to be formed in a medium.

Front 36

overtone

Back 36

the frequencies of vibration that are higher than the fundamental frequency and will cause a standing wave to be formed in a medium.

Front 37

beats

Back 37

the regular pulsing of loudness/quietness of a sound caused when two similar frequencies are played at the same time. The frequency of variation in loudness is called the beat frequency and is the difference between the two frequencies being played.