waves

Question 1

two types of waves

Answer 1

1. transverse
2. longitudinal

Question 2

what is a transverse wave

Answer 2

a wave for which the oscillations are perpendicular to the direction of energy transfer

Question 3

what is a longitudinal wave?

Answer 3

a wave for which the oscillations are parallel to the direction of energy transfer

Question 4

2 examples of transverse waves?

Answer 4

1. electromagnetic waves
2. seismic s-waves

Question 5

2 examples of longitudinal waves

Answer 5

1. sound waves
2. seismic p-waves

Question 6

what are two parts of a longitudinal waves called

Answer 6

compression and rarefactions

Question 7

what is a wave amplitude

Answer 7

the maximum displacement of a point on a wave from its undisturbed position

Question 8

what is wavelength?

Answer 8

the distance from a point on a wave to the same position on the adjacent wave
most commonly peak to peak to trough to trough

Question 9

what is the frequency of a wave

Answer 9

the number of waves that pass a given point each second

Question 10

what is the unit for frequency

Answer 10

Hz

Question 11

what is wave speed

Answer 11

the speed at which the wave moves or at which energy is transferred through a medium

Question 12

what does a wave transfer

Answer 12

energy

Question 13

wave speed calculation

Answer 13

wave speed = frequency x wavelength

Question 14

what word is used to describe when a wave bounces off a surface

Answer 14

reflection

Question 15

how do sound waves travel through a solid

Answer 15

the particles in the solid vibrate and transfer kinetic energy through the material

Question 16

what is the frequency range of human hearing

Answer 16

20Hz - 20kHz

Question 17

what are ultrasound waves

Answer 17

waves which have a frequency higher than the upper limit of human hearing

Question 18

example of an use for ultrasound waves

Answer 18

medical or industrial imaging

Question 19

what natural event causes seismic waves to be produced

Answer 19

earthquakes
they produce both p-waves and s-waves

Question 20

state a difference between the mediums that p-waves and s-waves can travel through

Answer 20

p-waves travel through both solids and liquids
s-waves only travel through solids not liquids

Question 21

what technique is used to detect objects in deep water and measure water depth

Answer 21

echo sounding
high frequency sound waves are emitted reflected and detected
time difference between emission and detection alongside wave speed and used to calculate distances

Question 22

what type of spectrum do electromagnetic waves form

Answer 22

a continuous spectrum

Question 23

order the types of electromagnetic radiation from lowest to highest frequency

Answer 23

• radiowaves
• microwaves
• infared
• visible light
• ultraviolet
• x-rays
• Gamma rays

Question 24

how do the speeds of em radiation differ in a vacuum and in the air

Answer 24

electromagnetic waves all travel at the same speed in a vacuum and in air

Question 25

what property of waves in different mediums causes refraction

Answer 25

- velocity - wave speed is slower in denser materials cause refraction

Question 26

in which direction do waves refract when entering a denser medium

Answer 26

the bend towards the normal the angle of refraction is less than the angle of incidence

Question 27

what type of waves can be produced by oscillations in an electrical circuit

Answer 27

radio waves

Question 28

how can radio waves create an alternating current in a circuit

Answer 28

when radio waves are absorbed, they can induce oscillations in a circuit with the same frequency as the waves themselves

Question 29

where do gamma rays originate from

Answer 29

they originate from changes in the nuclei of atoms

Question 30

what health issues can ultravoilet light cause

Answer 30

they can cause the skin to age prematurely increase the risk of developing skin cancer

Question 31

what health effects can x-rays and gamma rays cause

Answer 31

they are ionising radiation so can cause mutations in genes they can lead to increased risk of developing various cancers

Question 32

give 3 practical uses for infrared radiation

Answer 32

1. electrical heaters 2. cooking food 3. infrared cameras

Question 33

give 2 practical uses for microwave radiation

Answer 33

1. satellite communications 2. cooking food

Question 34

give 2 practical uses for radio waves

Answer 34

1. tv transmission 2. radio transmission

Question 35

what wave phenomena is used by lenses to form an image

Answer 35

refraction

Question 36

how does a convex lens form an image

Answer 36

parallel rays of light are refracted and brought together at a point known as the principle focus

Question 37

what is meant by the focal length of a lens

Answer 37

the distance from the lens to the principle focus

Question 38

what is the difference between the image produced by a convex and concave wave

Answer 38

convex lenses can produce real or virtual images concave lenses can only produce virtual images

Question 39

why does magnification not have a unit

Answer 39

it is the ratio between image height and object height ratios do not require units

Question 40

what determines the colour of visible light waves

Answer 40

the wavelength and frequency of the light waves

Question 41

what colour of visible light has the highest frequency

Answer 41

blue

Question 42

what colour of visible light has the largest wavelength

Answer 42

red

Question 43

what is meant by the term specula reflection

Answer 43

reflection from a smooth surface in a single direction

Question 44

what is meant by the term diffuse reflection

Answer 44

reflection from a rough surface which causes scattering

Question 45

how does a red colour filter work?

Answer 45

a red filter absorbs all wavelengths of light other than those in the red range spectrum this means only red light passes through the filter

Question 46

what determines the colour of an opaque object

Answer 46

different objects reflect different wavelengths of light by different amount the wavelengths that are most strongly reflected determine the colour

Question 47

what happens to the wavelengths of light that aren't reflected by an opaque object

Answer 47

any wavelength that aren't reflected are absorbed by the object

Question 48

what colour does an object appear if all wavelengths are reflected by equal amounts

Answer 48

white

Question 49

what colour does an object appear id all wavelengths are absorbed

Answer 49

black

Question 50

what do all bodies emit and absorb

Answer 50

infrared radiation

Question 51

what happens to the quantity of infrared radiation emitted by an object as temp increases

Answer 51

the hotter the object, the more infrared radiation it will emit

Question 52

what is a perfect black body huh

Answer 52

an object that absorbs all of the radiation that is incident upon it

Question 53

how much radiation does a perfect black body reflect or transmit

Answer 53

none

Question 54

why is a perfect black body the best possible emitter of radiation

Answer 54

it is a perfect absorber since it absorbs all radiation incident on it a perfect absorber is also a prefect emitter

Question 55

other than the intensity of radiation emitted, how does increasing the temp of an object affect its emissions

Answer 55

the wavelength distribution of an emission is dependent on the objects temp

Question 56

what can be said about the rates of emission and absorption for a body at constant temp

Answer 56

the body is absorbing and emitting radiation at the same rate

Question 57

what can be said about the rates of emission and absorption for a body increasing in temp

Answer 57

the body is absorbing radiation faster than it is emitting it

Question 58

give 2 facts that affect the temp of earth

Answer 58

the earths rate of absorption and emission of radiation the amount of reflection of radiation into space