topic 6: waves

Question 1

What are the two types of waves?

Answer 1

transverse
longitudinal

Question 2

What is a transverse wave?

Answer 2

Away for which the oscillations are perpendicular to the direction of energy transfer

Question 3

what is a longitudinal wave

Answer 3

Away for which the oscillations are parallel to the direction of the energy transfer

Question 4

Give two examples of transverse waves

Answer 4

electromagnetic waves
seismic s-waves

Question 5

Give two examples of longitudinal waves

Answer 5

sound waves
seismic p-waves

Question 6

What are the two parts of a longitudinal wave called?

Answer 6

compressions and rarefactions

Question 7

What is a wave amplitude?

Answer 7

The maximum displacement of a pint on a wave from its disturbed position

Question 8

what is a wavelength?

Answer 8

The distance from a point on a wave to the same position on the adjacent wave

Most commonly peak to peak or trough to trough

Question 9

What is a frequency of the wave?

Answer 9

The number of waves that passed a given point each second

Question 10

what unit is used for frequency?

Answer 10

hertz,Hz

Question 11

What is meant by frequency of 200 HZ?

Answer 11

200 waves past a given point each second

Question 12

What is a wave speed?

Answer 12

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

Question 13

What does a wave transfer?

Answer 13

Energy

Question 14

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

Answer 14

Reflection

Question 15

How do you sound waves travel through a solid?

Answer 15

The particles in a solid vibrate and transferred 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

give an example use for ultrasound waves

Answer 18

Medical or industrial imaging

Question 19

what natural event causes seismic waves to be produced? What types are produced?

Answer 19

Earthquakes

They produce both P waves and S waves

Question 20

State the 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

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 a mission and detection alongside wave speed are used to calculate distances

Question 22

what do our bodies emit and absorb?

Answer 22

Infrared radiation

Question 23

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

Answer 23

The hotter the object the more infrared radiation it will emit

Question 24

what is the perfect black body?

Answer 24

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

Question 25

how much radiation does a perfect black body reflect or transmit?

Answer 25

None

Question 26

why is a perfect black body the best possible emmiter of radiation? 

Answer 26

it is a perfect absorber since it absorbs our radiation incident on it A perfect absorber is also a perfect emmiter

Question 27

Other than the intensity of radiation omitted how does increasing the temperature of an object affect its emissions?

Answer 27

The wavelength for distribution of any emission is dependent on the object temperature

Question 28

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

Answer 28

The body is absorbing and emitting radiation at the same rate

Question 29

What can be said about the rates of emission and absorbing for a body increasing in temperature?

Answer 29

The body it is absorbing radiation faster than it is admitting it

Question 30

Give two factors that affect the temperature of the earth

Answer 30

The Earth rate of absorption and emission of radiation The amount of reflection of radiation into space

Question 31

what type of spectrum do electromagnet waves form?

Answer 31

A continuous spectrum

Question 32

Over types of electromagnetic radiation from lowest to highest frequency

Answer 32

Radio waves Microwave Infrared Visible light Ultraviolet X-rays Gamma rays

Question 33

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

Answer 33

Electromagnetic waves or travel at the same speed in a vacuum and in air

Question 34

What property of waves in different mediums causes refraction?

Answer 34

velocity Wave speed is slower in dense materials, causing refraction

Question 35

In which direction do ways refract when entering a dense medium

Answer 35

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

Question 36

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

Answer 36

Radio waves

Question 37

how can radio waves create an alternative current in a circuit?

Answer 37

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

Question 38

where do gamma rays originate from?

Answer 38

They originate from changes in the nuclei of atoms

Question 39

what health affects can ultraviolet waves cause?

Answer 39

It can cause a skin to age prematurely They can increase the risk of developing skin cancer

Question 40

what effects can x-rays and gamma rays cause

Answer 40

they are ionising radiation so can cause mutation in genes They can lead to increase risk of developing various cancer

Question 41

give three practical uses for infrared radiation

Answer 41

electrical heater Food cooking Infrared cameras

Question 42

Give two practical duties for microwave radiation

Answer 42

satellite communications Cooking food

Question 43

Two practical uses for radio waves

Answer 43

television transmission Radio transmission

Question 44

What wave phenomenon is used by lenses to form an image?

Answer 44

Refraction

Question 45

How does a convex lens form an image?

Answer 45

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

Question 46

what is meant by the focal length of a lens?

Answer 46

The distance from the lens to the principal focus

Question 47

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

Answer 47

Convex lenses can produce real or virtual images Conveyed lenses can only produce virtual images

Question 48

why does magnification not have a unit?

Answer 48

It is the ratio between image height and object height Ratios do not require Units

Question 49

What determines the colour of visible light waves?

Answer 49

The wavelength and frequency of the light waves

Question 50

what colour are visible light has the highest frequency

Answer 50

Blue

Question 51

What colour are visible light has the largest wavelength

Answer 51

red

Question 52

What is meant by the term specular reflection?

Answer 52

Reflection from a smooth surface in a single direction

Question 53

what is meant by the term diffuse reflection?

Answer 53

Reflection from a rough surface which causes scattering

Question 54

How does a red colour filter Work?

Answer 54

A red filter absorbs all wavelength of light other than those in the red range of the spectrum This means only red light passes through the filter

Question 55

what determines the colour of an opaque object?

Answer 55

Different objects reflect different wavelengths of light by different amounts The wavelengths that are the most strongly reflected determine the colour

Question 56

what happens to the wavelength of light that aren’t reflected by an opaque object?

Answer 56

Any wave lengths that aren’t reflected absorbed by the object

Question 57

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

Answer 57

White

Question 58

what colour does an object appear if all wavelengths are absorbed?

Answer 58

Black