3b P1 waves - speed and properties 3d LM

Question 1

what are the two types of waves?

Answer 1

longitudinal

transverse

Question 2

what are transverse waves?

Answer 2

waves where the points along its length vibrate at 90 degrees to the direction of energy transfer

Question 3

what are properties of transverse waves?

Answer 3

energy transfer is in the same direction as the wave motion
only transfers energy
move in a liquids and solids, not gas
some can move in a vacuum

Question 4

what are longitudinal waves?

Answer 4

waves where the points along its length vibrates parallel to the direction of energy transfer

Question 5

what are the properties of longitudinal waves?

Answer 5

energy transfer is in the same direction as the motion
only energy transfer
move in all things
can move in a vacuum

Question 6

what are the key features of longitudinal waves?

Answer 6

points where they are close together are called compressions

where it is spaced apart its called rarefactions

Question 7

what is a way to visualise the two types of waves?

Answer 7

transverse waves is like moving a rope up and down

longitudinal is like the vibrations of a coil

Question 8

where do you draw the normal in reflection?

Answer 8

90degrees to the mirror or the object

Question 9

where is the angle of incidence in reflection?

Answer 9

between the ray going in and the normal

Question 10

where is the angle of reflection in reflection?

Answer 10

between the ray going out and the normal

Question 11

where is the normal in refraction?

Answer 11

perpendicular to the object

Question 12

where is the angle of incidence in refraction?

Answer 12

between the ray going in and the normal

Question 13

where is the angle of reflection in refraction?

Answer 13

the refracted ray going into the object/water

Question 14

what is n in snells law?

Answer 14

the refracted index

Question 15

which wave changes density and pressure?

Answer 15

longitudinal, transverse waves don’t

Question 16

what is the Doppler effect?

Answer 16

the apparent change in wavelength and frequency of a wave emitted by a moving source

Question 17

explaining the Doppler effect?

Answer 17

when an object is stationary the waves emit symmetrically out from the source
when an object is moving the waves appear bunched up at the front of the moving object and spaced out at the back

Question 18

what is the critical angle?

Answer 18

in total internal reflection when the angle becomes big enough for it to be reflected out, the incident angle becomes the critical angle

Question 19

what’s total internal reflection?

Answer 19

it happens when light is moving from a denser medium to a less dense one when there is a large enough angle from the normal in refraction it reflects in a glass object instead of coming out at the other end

Question 20

what wave is light?

Answer 20

transverse waves

Question 21

what can light waves undergo?

Answer 21

reflection and refraction

Question 22

what waves are sound?

Answer 22

longitudinal

Question 23

what can sound waves undergo?

Answer 23

reflection and refraction

Question 24

what ray is the incident ray?

Answer 24

the ray going in

Question 25

what ray is the refracted ray?

Answer 25

the ray going out

Question 26

why do waves change direction?

Answer 26

because when they move through materials with different densities they can change direction

Question 27

what are the i and r angles equal too?

Answer 27

each other

angle of incidence = angle of reflection

Question 28

what happens when a light travels from dense to more dense materials?

Answer 28

light bends toward the normal

Question 29

what happens when a light travels from more dense to less dense materials?

Answer 29

light bends away from the normal

Question 30

in refraction where does the light refract entering the block?

Answer 30

the light ray refracts toward the central line

Question 31

in refraction where does the light refract when exiting the block?

Answer 31

the light ray refracts away from the central line

Question 32

what are the two conditions needed for total internal reflection?

Answer 32

the angles of incidence > the critical angle

the incident material is denser than the second material

Question 33

what is an oscilloscope?

Answer 33

a device that can be used to study a rapidly changing signal
such as
a sound wave
an alternating current

Question 34

what is the pitch of a sound?

Answer 34

the pitch of the sound is related to the frequency of the sound waves
low wave freq is low pitch
high wave freq is high pitch

Question 35

what is the loudness of a sound?

Answer 35

its related to the amplitude of a vibrating source of sound waves
higher amplitude = louder sound

Question 36

what is the range of human hearing?

Answer 36

20 - 20000 Hz