Waves

Question 1

what can waves transfer and what does it not

Answer 1

energy and information without transferring matter

Question 2

what 5 pieces of data can be used to describe a wave

Answer 2

frequency
speed
wavelength
amplitude
period

Question 3

what is wavelength

Answer 3

the distance from one crest of a wave to another

Question 4

what is the amplitude

Answer 4

the distance from the top of a wave to the middle

Question 5

what are the 2 types of waves

Answer 5

longitudinal
transverse

Question 6

what are 2 examples of longitudinal waves

Answer 6

sound waves
seismic P waves

Question 7

what is a longitudinal wave

Answer 7

where the particles move back and forth along the direction the sound is travelling

Question 8

what are 2 examples of a transverse wave

Answer 8

EM waves
seismic S waves

Question 9

what is a transverse waves

Answer 9

where the particles move at right angles to the direction the waves are travelling

Question 10

what is the formula for the period

Answer 10

1/frequency

Question 11

what are the 2 equations that can be used to find the speed of a wave

Answer 11

speed = distance/time
speed = frequency * wavelength

Question 12

what are 2 ways to measure wave velocity in air

Answer 12

using an echo
using 2 microphones and an oscilloscope

Question 13

what 2 tools are used to measure the speed of ripples on the water surface

Answer 13

ripple tank
strobe light

Question 14

what 4 things can happen to a wave when it hit a boundary

Answer 14

reflected
refracted
absorbed
transmitted

Question 15

when are sound waves transmitted

Answer 15

when the densities of the 2 materials are similar

Question 16

when are sound waves absorbed

Answer 16

when the material absorbs sound waves

Question 17

when are sound waves reflected

Answer 17

big difference in densities

Question 18

why do sound waves get refracted

Answer 18

when they move between materials of different materials which causes different parts of the wave to slow down and change direction

Question 19

how are sound waves created

Answer 19

when an object vibrates

Question 20

what is the human hearing range

Answer 20

20Hz - 20’000Hz

Question 21

how does the ear work

Answer 21

1. sound waves travel down the ear canal
2. sound wave hits ear drum skin
3. the compression and decompression of the air particles cause the eardrum to vibrate
4. the vibrations are converted into electrical signals

Question 22

what are the 2 types of sound waves

Answer 22

ultrasound
infrasound

Question 23

what is ultrasound

Answer 23

sound waves with a frequency higher than 20’000Hz

Question 24

what is infrasound

Answer 24

waves with a frequency lower than 20Hz

Question 25

what are 2 uses of ultrasound

Answer 25

• used to make images of the inside of the body such as scans of babies
• used in sonar

Question 26

what are 2 uses of infrasound

Answer 26

• track the path of meteors
• determine rock structure beneath the earth’s crust

Question 27

how is ultrasound used in prenatal scans

Answer 27

the ultrasound is harmless and can be sent into the body. it will be reflected when it meets tissues with different densities. a scanner can detect the echoes and use it to create an image

Question 28

how is ultrasound used in sonar

Answer 28

uses of pulses of ultrasound that are sent towards the seabed. and equipment is used to measure the time between sending the sound and detecting its echoes so that the distance to the seabed and the depth can be calculated

Question 29

when are sound waves the fastest and why

Answer 29

in solids, the highest densities