Waves

Question 1

what is a progressive wave?

Answer 1

waves that transfer enery (from one point to another)

Question 2

true or falce. waves tranfer energy but not matter

Answer 2

True

Question 3

What is a non-progressive wave?

Answer 3

stationary or standing wave

Question 4

waves consist of pulses what is a pulse?

Answer 4

one pulse is the aria under one hump on a graph of a wave

Question 5

what is a pulse or wave caused by?

Answer 5

the disturbance of a medium

Question 6

true or falce. waves do not consist of matter they travel through a medium

Answer 6

true

Question 7

what is a Transverce wave?

Answer 7

a wave where the direction of motion (energy transfered) is perpendicular to the direction of disturbance

Question 8

what is displacment of a wave?

Answer 8

the difference between the x acis and the wave

Question 9

what is the wavelength?

Answer 9

the distance between two consicitive points on a wave with the same orientation

Question 10

what are crests and troughs?

Answer 10

a crest is the highest point of the wave and a trough is the lowest point of a wave

Question 11

what is the amplitude?

Answer 11

the maximum displacement

Question 12

what is wavelength mesured in?

Answer 12

meters

Question 13

define Frequency (f)

Answer 13

the number of complete ossolations/cycles per second (messured in Hz)

Question 14

define Period (T)

Answer 14

Time Taken for one complete cycle/oscillation (messured in seconds)

Question 15

what is period equal to in terms of frequency

Answer 15

period = 1/frequency
T = 1/f

Question 16

what is frequency equal to in terms of period

Answer 16

frequency = 1/period
f = 1/T

Question 17

how do yo find speed of a wave?

Answer 17

V = wavelenght x frequency

Question 18

define phase difference

Answer 18

by how much (degrees, rad or wavelengths) one point on a wave is ahead of another
or
one wave is ahead of another

Question 19

true or falce. to calculate the phase difference between two waves they must have the same frequency

Answer 19

True

Question 20

true or falce. for two waves to be in phase there crests troughts and x axis intersections must all happen that the exact same time

Answer 20

True

Question 21

what is an inverce wave

Answer 21

the reflection of a wave across the x axis

Question 22

in a cathode ray ocilliscope (CRO) what does the y axis represent?

Answer 22

the voltage or current

Question 23

in a cathode ray ocilliscope (CRO) what does the x axis represent?

Answer 23

time

Question 24

what is one block on a cathode ray ocilliscope (CRO)?

Answer 24

one time base (messured in millie seconds)

Question 25

what is intencity deffinition?

Answer 25

the amount of energy per unit time that passes through a unit aria Intencity = power/aria

Question 26

what is intencity proportional to?

Answer 26

Aria^2 or Frequency^2

Question 27

define a sperical wave

Answer 27

a wave from a point sorce which spreads out equaly in all directions Intencity = power/(4 pi r^2)

Question 28

what are some examples of transverse waves?

Answer 28

electromagnetic waves: radio, visible light, UV vibrations on gituar string (not sound) can be shown on rope

Question 29

can transverce waves be polorised?

Answer 29

yes

Question 30

what do longatudinal waves have instead of crests and troughs?

Answer 30

rarefactions and compressions

Question 31

true or falce. all waves can be difracted

Answer 31

True

Question 32

can longitudinal waves be polorised?

Answer 32

no

Question 33

give two examples of longaudinal waves

Answer 33

sound and ultrasound

Question 34

define the doppoler effect/shifft

Answer 34

when the percived frequency or pitch of a wave (sound or ligh) is different to the actual frequency emitted due to the relative motion of the observed and/or sorce

Question 35

what will you hear when a car is speeding towards you and why

Answer 35

you will hear an increce in pitch due to the sound waves being compressed in front of the car (more ossilations reaching you per second (Hz))

Question 36

what will happen when a car speeds passed you and why

Answer 36

after the car passes you the pitch will drop drasticaly as the waves now expand towards you (less ossilations per second(Hz))

Question 37

what is the equation for the doppoler effect?

Answer 37

observed frequency = sorce frequency (wave velocity / (wave velocity +- sorce velocity))

Question 38

ROYGBIV is the visible light on the electromagnetic spectrum. what does it stand for?

Answer 38

Red Orange Yellow Green Blue Indigo Violate

Question 39

does wavelength increce towards the red end of the electromagnetic spectrum?

Answer 39

yes

Question 40

does frequency increce towards the blue end of the electromagnetic spectrum?

Answer 40

yes

Question 41

what are proporties of electromagnetic waves?

Answer 41

all transverce can travel in vaccume travel at 3x10^8 m/s (speed of light) they are self propogating (dont need a medium)

Question 42

What is the wavelength and frequency of the first harmonic (fundamental) wave in a closed Columb? and how many nodes and anti nodes does it have?

Answer 42

wavelength: 2L Frequency: C/2L 2 Nodes (one at each end) and 1 antinode

Question 43

what is the wavelength and frequency of the second harmonic wave in a closed columb? and how many nodes and anti nodes does it have?

Answer 43

wavelength: L Frequency: c/L 3 nodes and 2 anti nodes

Question 44

what is the wavelength and frequency of the third harmonic wave in a closed Columb? and how many nodes and anti nodes does it have?

Answer 44

wavelength: 2L / 3 frequency: 3c / 2L 4 nodes 3 anti nodes

Question 45

True or false. the n-th harmonic has n-antinodes and n+1 nodes

Answer 45

True

Question 46

explain the principle of superposition

Answer 46

when two or more waves meet the resultant displacement is the vector sum of the displacement of the individual waves

Question 47

state the equation for superposition

Answer 47

where: A = amplitude A1 + A2 = A-resiltant

Question 48

true or false. all types of waves including transverse and longitudinal can undergo super position

Answer 48

True

Question 49

define polarization

Answer 49

when a wave is forced to only oscillate in one plain only due to a screen

Question 50

regarding waves in an air column, what will happen if one or the ends are open

Answer 50

an antinode will form at any open end

Question 51

what does a lower harmonic do to the frequency and pitch of a wave

Answer 51

lower harmonic means lower frequency and lower pitch

Question 52

state Malus's law

Answer 52

I = I1 cos^2 (x) Where: I = intensity of light through the analyzer I1 = intensity of polarised light x = angle between transmission axis and polariser

Question 53

define interference in therms of waves

Answer 53

when two waves meet the resultant displacement (amplitude) is the sum total of the individual displacments

Question 54

when does constructive interference occur?

Answer 54

when the waves are in phase

Question 55

when does deconstructive interference take place?

Answer 55

when waves are in antiphase

Question 56

true or false microwaves undergo two-phase interferance

Answer 56

True

Question 57

what does the path diff equal for constructive interference?

Answer 57

path diff = n wavelenth

Question 58

what does the path diff equal for destructive interference?

Answer 58

path diff = (n + 1/2) wavelenth

Question 59

define coherance

Answer 59

waves with the same frequency and constant phase difference

Question 60

does a lamp produce coherent light?

Answer 60

yes

Question 61

define diffraction

Answer 61

the bending and spreading out of a wave when it encounters an obstacle or gap in obstacle

Question 62

true or false when the wavelength is bigger than the gap we have more diffraction

Answer 62

true

Question 63

true or false when the wavelength is smaller than the gap we have less diffraction

Answer 63

True

Question 64

True or false diffraction only effects the amplitude of the wave

Answer 64

True

Question 65

what is diffraction?

Answer 65

the bending and spreading out of waves

Question 66

what is a diffraction grating?

Answer 66

an optical instrument used to cause a diffraction pattern when it diffracts monochromatic light into bright and dark fringes

Question 67

what does a diffraction grating consist of?

Answer 67

a large number of very thin equally spaced parallel slits carved into a glass plate

Question 68

true or false. in a diffraction screen points of maximum interference are also points of maximum intensity

Answer 68

True

Question 69

what is the diffraction grating equation?

Answer 69

d sin(x) = n (lambda) Where: d = spacing between slits x = angular separation between the order of maxima (degrees) n = order of minima (1, 2, 3, ...) lambda = wavelength of light source