Waves

Question 1

What is amplitude

Answer 1

half the crest to trough distance

Question 2

what is wavelength

Answer 2

the distance between any part of the wave and the next part where the wave repeats itself

Question 3

what is frequency

Answer 3

the number of waves produced in 1 second

Question 4

what is period

Answer 4

the time it takes to make 1 wave

Question 5

what is a wavefront

Answer 5

a line joining together similar points on a wave

Question 6

what are transverse waves

Answer 6

Waves that vibrate or oscillate perpendicular to the direction of energy transfer

Question 7

what are longitudinal waves

Answer 7

oscillations occur parallel to direction of energy

Question 8

what is frequency measured in

Answer 8

Hertz (Hz)

Question 9

what is the doppler effect

Answer 9

The apparent change in observed wavelength and frequency of a wave emitted by a moving source relative to an observer

Question 10

what is the electromagnetic spectrum (in order shortest - longest)

Answer 10

gamma rays
x - rays
ultraviolet
visibe
infared
microwaves
radio

Question 11

what is the electromagnetic spectrum for light (in order shortest - longest)

Answer 11

indigo
blue
green
yellow
orange
red

Question 12

what kind of waves are light waves

Answer 12

transverse waves

Question 13

what can be done light waves

Answer 13

they can be reflected and refracted

Question 14

what is the law of reflection

Answer 14

angle of incidence = angle of reflection

Question 15

explain the image in a mirror

Answer 15

images are formed when the light ray bouncing off of an object onto a mirror are diverging so they light from the object appears to be in a different place

Question 16

what bends twards the normal

Answer 16

light going from air to glass

Question 17

what bends away from normal

Answer 17

light going from glass to air

Question 18

what is the cirtical angle

Answer 18

the angle of incidence for which the angle of refraction is 90 degrees

Question 19

what is total internal relfection

Answer 19

if the angle of incidence is larger than the cirtical angle

Question 20

what are examples of total internal reflection

Answer 20

periscope
endoscope
fiber optics

Question 21

what kind of wave is a sound wave

Answer 21

longitudinal wave

Question 22

how can a sound wave be refracted

Answer 22

if it travels from one density (temperature) to another

Question 23

what does high frequency mean

Answer 23

a sound with a high pitch

Question 24

what is the range of human hearing

Answer 24

20Hz - 20000 Hz

Question 25

what does it mean if the wave is further apart

Answer 25

quite and low pitched

Question 26

what does it mean if the waves are close together

Answer 26

loud and high pitched

Question 27

how can you investigate the speed of sound

Answer 27

using a clapper board one person stands away and they start the stopwatch when they see the clapper board touch and then stop when they hear the sound

Question 28

how are microwaves a hazard

Answer 28

they can cause internal heating of body tissues

Question 29

how is ultraviolet light a hazard

Answer 29

increases the rish of skin cancer and blindness

Question 30

what are radio waves used for

Answer 30

radio and television communications

Question 31

what are microwaves used for

Answer 31

satellite transmissions and cooking

Question 32

what is infared radiation used for

Answer 32

heaters and night vision equipment

Question 33

what is visible light used for

Answer 33

fibre optics and photography

Question 34

what is ultraviolet used for

Answer 34

fluorescent lamps

Question 35

what are x - rays used for

Answer 35

medical imaging and security

Question 36

what is gamma radiation used for

Answer 36

sterillising food and medical equipment

Question 37

what is different of how waves transfer energy

Answer 37

they only transfer energy and not particles

Question 38

ways where we can observe the doppler effect

Answer 38

The frequency of the sound waves emitted by ambulance or police sirens goes from a high pitch (high frequency) to a low pitch (low frequency) as the vehicle whizzes past Galaxies in outer space emit light waves which appear redder (longer wavelength) to an observer on Earth because the stars are moving away from us

Question 39

draw a ray diagram for the reflection of light

Answer 39

Question 40

what is refraction

Answer 40

when a wave slows down or speeds up at a boundary between two materials

Question 41

draw a ray diagram for a refracted light ray

Answer 41

Question 42

what is a part of the electromagnetic specturm that includes everything

Answer 42

ight is part of a continuous electromagnetic spectrum that includes radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations and that all these waves travel at the same speed in free space

Question 43

what are the dangers of infared radiation

Answer 43

skin burns

Question 44

what are the dangers of gamma rays

Answer 44

cancers and mutation

Question 45

how to protect yourself againsts dnagerous electromagnetic waves

Answer 45

ultraviolet - sunscreen, sunglasses gamma and x rays - use low levels and avoid uneccesary contact infared - wear protective clothing

Question 46

what is the investigation for the refraction of light

Answer 46

investigating useing rectangular blocks, semi circular blocks and triangular prisms

Question 47

results from investigating the refraction of light

Answer 47

when light travels from one medium to another medium, it changes its path this is because the speed of light will change.

Question 48

what is the experiment for the refractive index of glass

Answer 48

passing rays of light through a glass box to find the refractive index of glass

Question 49

set up for investigaing the refractive index of glass

Answer 49

Question 50

what are optical fibres

Answer 50

they are made of plastic or glass and consist of a central core surrounded by coating with a lower refractive index

Question 51

how do optic fibres work

Answer 51

the core of the fibre is so narrow that light signals passing through it always hit the core cating boundary so the light is always internally reflecting

Question 52

what is an oscilloscope

Answer 52

a device which can display the microphone signal as a trace on a screen

Question 53

how does the ocilloscope display sound waves

Answer 53

the appreance of the wave on the screen tells you weather it is loud or quite and high or low pitched. you can take detailed measurements to calculate the frequency by adjusting the settings of the display

Question 54

draw the 4 common traces from an oscilloscope

Answer 54

Question 55

how does pitch and sound relate to frequency

Answer 55

A high pitch sound corresponds to a high frequency sound wave a low pitch sound corresponds to a low frequency sound wave

Question 56

how does loudness of sound relate to the amplitude of vibration

Answer 56

The greater the amplitude the louder the sound. Bigger vibrations of a sting mean more energy is being put in so more energy out as sound waves.