Flashcards

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veralee.art Inglês 17 flashcards

Flashcards do conjunto (17)

1SoundA form of energy, produced by rapidly vibrating objects, that can be heard by the human ear
2InfrasonicAny sound with a frequency lower than the threshold of human hearing (20 Hz)
3UltrasonicAny sound with a frequency above the threshold of human hearing
4What are all sounds caused byVibrations
5What is the human range of hearing20 - 20000 hz
6What does sound need for transmission?A material medium- cannot travel through a vacuum
7Compressionwhen molecules bump into their neighbors due to a vibration, a steadily moving area of collision (the compression) is created
8RarefactionRegion of emptiness into which the displaced air molecules rebound. (Follows a compression outwards)
9How does sound travel out from its source?In a longitudinal wave
10If an amplitude is larger...The sound is louder
11Pitchthe perception of the highness or lowness of a sound; depends primarily on the frequency of the sound
12Speed of sound in airV=332(0.59T)
13Sound intensitypower of sound per unit (watts/ m^2)
14Sound intensity depends on...The vibrational energy of the source
15decibel (dB)Unit used to measure the sound intensity level
16EchoReflected Sound wave
17Diffractionability of waves to move around an obstacle or to spread out after going through a small opening