4.2

Question 1

sound

Answer 1

produced when something vibrates, moving back and forth very quickly

Question 2

compressions

Answer 2

region of high pressure in which particles are close together (bunched up)

Question 3

rarefactions

Answer 3

a region of low pressure in which particles are far apart (spread-out)

Question 4

soundwave

Answer 4

movement of alternating compressions and rarefactions, usually travels away from source.

Question 5

waves

Answer 5

carries energy from one point to another

Question 6

transverse waves

Answer 6

particles of the wave vibrate up and down

Question 7

longitudinal waves

Answer 7

particles move in same direction that the wave is moving

Question 8

echo

Answer 8

reflected sound and heard a second time

Question 9

sonar

Answer 9

technique that calculates the depth of subjects underwater

Question 10

reverberation

Answer 10

length of time a sound can be heard for (harder surface=longer)

Question 11

oscilloscope

Answer 11

compares different sounds by analysing sound waves

Question 12

frequency

Answer 12

number of vibration a sound makes each second, high frequency have higher pitch

Question 13

hertz

Answer 13

measures frequency

Question 14

ultra sound

Answer 14

sound waves with frequencies above humans’ hearing range

Question 15

infrasound

Answer 15

frequencies lower than humans’ hearing range