P3 - Waves

Question 1

definition of waves

Answer 1

transfers energy outwards from a source, through a medium, without the movement of matter and particles

Question 2

definition of electromagnetic waves

Answer 2

consists of oscillating electric and magnetic field with no medium required. It travels fastest in a vacuum

Question 3

definition of mechanical waves

Answer 3

transfer of energy through oscillation of particles (medium is required). It travels faster in a denser medium

Question 4

definition of transverse waves

Answer 4

direction of vibration is perpendicular to the direction of energy transfer (propagation)

Question 5

what does the type of wave depend on?

Answer 5

direction of oscillation

Question 6

give 3 examples of transverse waves

Answer 6

-electromagnetic radiation
-water waves
-seismic secondary waves

Question 7

definition of longitude waves

Answer 7

direction of vibration is parallel to the direction of energy transfer (propagation)

Question 8

give 2 examples of longitudinal waves

Answer 8

-sound waves
-seismic primary waves

Question 9

definition of wavelength

Answer 9

distance between trough/crest of wave and next trough/crest

Question 10

what is the energy if the wavelength is low?

Answer 10

high

Question 11

what should the x axis be for the wavelength to be

Answer 11

distance/displacement

Question 12

definition of amplitude

Answer 12

how big the oscillation around the mean is

Question 13

what are 3 things that happen when there is a high amplitude?

Answer 13

-more energy
-loudness increases
-water waves move more

Question 14

definition of frequency

Answer 14

number of troughs that pass through a certain point each second

Question 15

what happens to the energy when there is a higher frequency?

Answer 15

more energy

Question 16

definition of time period

Answer 16

time taken to complete 1 cycle

Question 17

what should the x axis be for time period to be?

Answer 17

time

Question 18

what happens to the frequency and wavelength when a wave changes medium?

Answer 18

frequency stays the same
wavelength changes

Question 19

where is the speed of light fastest?

Answer 19

in vacuum

Question 20

where is sound fastest?

Answer 20

dense medium

Question 21

why is it called electromagnetic waves?

Answer 21

wave consists of electro and magnetic fields

Question 22

what is the speed of electromagnetic waves in a vacuum/air?

Answer 22

high speed - 3x10^8 m/s

Question 23

state the electromagnetic spectrum from least to most energy

Answer 23

radio –> micro –> infrared –> visible –> ultra-violet –> x-ray –> gamma

Question 24

radio waves have the highest/longest …?

Answer 24

wavelength

Question 25

gamma rays have the highest ...? and most ...?

Answer 25

highest frequency most energy

Question 26

state 3 uses of radio waves

Answer 26

-radio -television transmissions -radar

Question 27

state 3 uses of microwaves

Answer 27

-satellite television -mobile phone -microwave ovens

Question 28

state 2 uses of infrared waves

Answer 28

-remote controllers for televisions -thermal imaging

Question 29

state 2 uses of visible waves

Answer 29

-vision -photography

Question 30

state 1 use of ultra violet waves

Answer 30

detecting fake bank notes

Question 31

state 2 uses of x-ray waves

Answer 31

-medical scanning -security scanners

Question 32

state 2 uses of gamma ray waves

Answer 32

-detection of cancer -cancer treatment

Question 33

state 3 harmful effects of ultra-violet

Answer 33

-damage to surface cells and eyes -can lead to skin cancer -can lead to eye conditions

Question 34

state 1 harmful effect of x-ray waves

Answer 34

mutation/damage to cells in the body

Question 35

state 1 harmful effect of gamma ray waves

Answer 35

mutation/damage to cells in the body

Question 36

cause of harmful effects on people (electromagnetic spectrum)

Answer 36

excessive exposure to electromagnetic radiation

Question 37

what is sound produced by?

Answer 37

vibrating sources

Question 38

what are longitudinal nature of sound waves in air?

Answer 38

series of compressions and rarefactions

Question 39

definition of compressions

Answer 39

regions of higher pressure because particles are closer together

Question 40

definition of rarefactions

Answer 40

regions of lower pressure because the particles are spread further apart

Question 41

whats the range of frequencies audible to humans?

Answer 41

20Hz - 20kHz

Question 42

what is needed to transmit sound waves

Answer 42

medium

Question 43

sound travels fast in ...,then ..., then ....

Answer 43

solid, then liquid, then gas

Question 44

what do the changes in amplitude and frequency affect?

Answer 44

loudness and pitch of sound waves

Question 45

definition of echo

Answer 45

reflection of a sound wave

Question 46

definition of ultrasound

Answer 46

sound with a frequency higher than 20kHz