waves

Question 1

what is the definition of waves

Answer 1

the transfer of energy from one point to another, involving oscillations. it doesn’t involve transfer of matter

Question 2

what is the definition of displacement

Answer 2

how far from the equilibrium point the wave has oscillated

Question 3

what is the definition of distance

Answer 3

how far the wave has travelled from its starting point

Question 4

what is the definition of amplitude

Answer 4

the height of a wave peak, measured from the central point of the oscillation

Question 5

what is amplitude measured in

Answer 5

metres, m

Question 6

what is the definition of a wavefront

Answer 6

an imaginary surface that represent the vibrating part of a wave

Question 7

what is the definition of a wave length

Answer 7

the distance between a point on one wave and the same point on the next wave

Question 8

what is wave length measured in

Answer 8

metres, m

Question 9

what is the definition of frequency

Answer 9

the number of waves passing a point per second

Question 10

what is frequency measured in

Answer 10

Hertz, Hz

Question 11

what is the definition of period

Answer 11

the time it takes for one complete wave to pass a point

Question 12

what is period measured in

Answer 12

seconds, s

Question 13

what is the definition of transverse waves

Answer 13

the oscillations are perpendicular to the direction of energy transfer

Question 14

examples of transverse waves

Answer 14

• light waves
• electromagnetic waves
• ripples on the surface of water
• vibrations in a guitar string

Question 15

what is the definition of longitudinal waves

Answer 15

the oscillations are parallel to the direction of energy transfer

Question 16

what is the definition of compression

Answer 16

the section of a longitudinal wave in which particles are close together

Question 17

what is the definition of rarefraction

Answer 17

the section of a longitudinal wave in which particles are spread apart

Question 18

examples of longitudinal waves

Answer 18

• sound waves
• ultrasound waves
• vibrations on a spring

Question 19

what is the equation for wave speed

Answer 19

velocity = wavelength x frequency

Question 19

what is the equation for Frequency

Answer 19

frequency = 1 / period

Question 20

what are the electromagnetic spectrum

Answer 20

• radio waves
• microwaves
• infrared radiation
• visible light
• ultraviolet
• X - rays
• Gamma rays

Question 21

what is Radio waves used for

Answer 21

communication and broadcasting

Question 22

detrimental effects of radio waves

Answer 22

none

Question 23

what is microwaves used for

Answer 23

cooking food and satellite communications

Question 24

detrimental effects of microwaves

Answer 24

internal heating of body tissue

Question 25

what is infrared radiation used for

Answer 25

- heaters - night vision equipment - cookers

Question 26

detrimental effects of infrared radiation

Answer 26

burns skin

Question 27

what is visible light used for

Answer 27

- optical figures - photography - fibre optic communications,

Question 28

detrimental effects of visible light

Answer 28

none

Question 29

what is ultraviolet used for

Answer 29

fluorescent lamps and energy - efficient lamps

Question 30

detrimental effects of ultraviolet

Answer 30

damages the surface cells causing the skin to tan or burn. blindness

Question 31

what is X - rays used for

Answer 31

observing the internal structure of objects and materials

Question 32

detrimental effects of X - rays

Answer 32

cancer and cell mutation

Question 33

what is Gamma rays used for

Answer 33

sterilising food and medical equipment

Question 34

detrimental effects of Gamma rays

Answer 34

cancer and mutation

Question 35

which wave has the longest wavelength in the electromagnetic spectrum

Answer 35

radio waves

Question 36

which wave has the lowest frequency in the electromagnetic spectrum

Answer 36

radio waves

Question 37

which wave has the lowest energy in the electromagnetic spectrum

Answer 37

radio waves

Question 38

which wave has the shortest wavelength in the electromagnetic spectrum

Answer 38

Gamma rays

Question 39

which wave has the highest frequency in the electromagnetic spectrum

Answer 39

Gamma rays

Question 40

which wave has the highest energy in the electromagnetic spectrum

Answer 40

Gamma rays

Question 41

similarities of transverse and longitudinal waves

Answer 41

- both transfer energy without transferring matter - involve continuous oscillations

Question 42

how is microwaves suitable for cooking food

Answer 42

- able to penetrate into food - water molecules in food absorb microwaves - causing them to vibrate and heat the food

Question 43

what do you do to convert MHz to Hz

Answer 43

multiply by 1 x 10^6

Question 44

how does X-rays shows the structure of bones

Answer 44

- the bones absorb the X - rays, leaving the film white in these areas - X - rays can penetrate tissues and be absorbed by the film

Question 45

how is infrared suitable for thermal imaging cameras

Answer 45

- the higher the temperature, the greater amount of infrared radiation it emits - thermal imaging camera absorbs the infrared radiation and shows the difference in temperature with different colours

Question 46

how to convert mm to m

Answer 46

divide by 1000

Question 47

how is radio waves suitable for communication

Answer 47

- transmitted easily through air - conductor absorbs the radio waves creating an alternating current. it has the same frequency as radio waves - information coded before wave transmission and decoded after receiving it

Question 48

how is visible light used in fibre optic communications

Answer 48

coded pulses of light waves travel through glass fibres from the source to the receiver

Question 49

how is ultraviolet used in energy - efficient lamps

Answer 49

the lamps absorb ultraviolet light produced inside the lamp, and re-emit the energy as visible light