Waves 1

Question 1

What is a progressive wave?

Answer 1

An oscillation that travels whilst transferring energy from one place to another without moving matter

Question 2

Explain the movement of particles when a wave passes through it.

Answer 2

Displaced from equilibrium position to new position - displaces near-by particles - these exert restoring force that moves origional particle to equilibrium

Question 3

What direction of partilces move in transverse waves?

Answer 3

Perpendicular

Question 4

Describe properties of transverse and logitudinal waves.

Answer 4

Trasverse - Energy is perpendicular, peaks and troughs
Logitudinal - Energy is parallel, refractions and compressions

Question 5

What is the definition of displacement?

Answer 5

Distance in a direction. (m)

Question 6

What is the defintion of amplitude?

Answer 6

The max displacement of the wave. (m)

Question 7

What is the defintion of wavelength?

Answer 7

The minimum distance betweem adjacent in-phase points. (m)

Question 8

What is the definition of period of oscillation?

Answer 8

Time taken to complete one oscillation. (s)

Question 9

What is the definition of frequency?

Answer 9

The number of oscillations that pass through a certain point per time. (Hz)

Question 10

What is the definition of wave speed?

Answer 10

The distance travelled by a wave per time. (m/s)

Question 11

What graph represents a wave profile? What can you find with one?

Answer 11

Displacement-distance graph.
Ampitude and wavelength

Question 12

What properties can you find with a displacement-time graph?

Answer 12

Period and amplitude.

Question 13

What is the defintion of phase difference?

Answer 13

The difference in displacements of partciles along a wave.

Question 14

If two partciles have zero phase difference, what are the points known as?

Answer 14

In-phase

Question 15

How much of a wavelength is 2pie radians?

Answer 15

Whole wavelength.

Question 16

If particles are in antiphase what does this mean?

Answer 16

Particles are in opposite oscillating patterns.

Question 17

Draw a displacement-distance and displacement-time graph to remind yourself.

Answer 17

Check online

Question 18

What happens when a wave relfects?

Answer 18

Wave changes direction at a boundary of two media, remaining in the original one.

Question 19

What is the Law of Reflection?

Answer 19

Angle of incidence = Angle of reflection

Question 20

How do we represent wave movements? How are the rays drawn?

Answer 20

Using wavefronts (peak of each wave).
Rays are drawn perpendicular.

Question 21

What else happens when a wave refracts?

Answer 21

Partial reflection.

Question 22

If the wave slows down, what way does the wave refract?

Answer 22

Refracts towards the normal

Question 23

Does refraction affect frequency?

Answer 23

No

Question 24

Does refraction affect wavelength?

Answer 24

Yes, as speed changes

Question 25

What happens when a wave enters deep water?

Answer 25

Wave speeds up, refract away from normal, wavelength increases.

Question 26

Name what these symbols stand for. n,c,v

Answer 26

n = refractive index c = speed of light in vacuum v = speed of light in medium

Question 27

What is snell's Law?

Answer 27

n1sin1 = n2sin2

Question 28

Where is the refractive index 1?

Answer 28

Air and vacuum.

Question 29

Why cant light microscopes go into too much detail?

Answer 29

Light diffracts so smaller components cannot be seen

Question 30

What is diffraction? What properties does it effect?

Answer 30

When a wave passes through a gap or around an object. None. Speed, wavelength, frequency remain the same.

Question 31

When is diffraction the greatest?

Answer 31

When the size of the gap or object is similar to the wavelength.

Question 32

What is the reflection of sound waves?

Answer 32

Echos

Question 33

What does it mean if a wave is polarised?

Answer 33

Particles oscillate on the plane of oscillation, in one direction only.

Question 34

What does plane polarised mean?

Answer 34

A wave that has been polarised.

Question 35

If ploarising filters are at 90 degrees....?

Answer 35

Stops all waves from passing through.

Question 36

Are all waves polarised?

Answer 36

No. Natual waves are usually not polarised.

Question 37

Why can longitudinal waves be plane polarised?

Answer 37

The oscillations are parallel. ??

Question 38

What does it mean if a wave is partially polarised and when can this happen?

Answer 38

Most poarticles are oscillating in one plane, but few in others. When reflecting off a surface.

Question 39

Give one use of polarising filters?

Answer 39

Sunglasses to stop glare frm surfaces such as lakes.

Question 40

What happens to intensity as a wave progresses?

Answer 40

Decreases.

Question 41

How does power spread as a wave progresses?

Answer 41

Uniformly in all directions. Sphere.

Question 42

What is intensity directly and inversely proportional to?

Answer 42

amplitude squared area

Question 43

What formula means that if we double the amplitude, the intensity will quadruple?

Answer 43

Intensity = (amplitude)^2

Question 44

Explain what happens to kinetic energy when we drop smth in water.

Answer 44

Half amplitude, half speed, quator kinetic energy

Question 45

How fast do EM waves travel?

Answer 45

Speed of light in a vacuum.

Question 46

What EM waves do and dont ionise?

Answer 46

DO NOT - radiowaves, microwaves, infrared and visible light DO - ultraviolet, x-rays, gamma

Question 47

Why cant all EM waves realise ionising radiation?

Answer 47

Not enough photon energy to remove electrons frm their shells ??

Question 48

Explain 3 types of ultraviolet light

Answer 48

WRITEEEEE

Question 49

What is the refractive Index for refractive glass?

Answer 49

1.5

Question 50

Why do diamond sparkle? What is its refractive index?

Answer 50

Total Internal Reflection. One of the highest refractive index of all natural materials.

Question 51

What are the conditions for TIR?

Answer 51

1. n1 > n2 2. Incident angle > critical angle

Question 52

What is the critical angle?

Answer 52

The angle and which the refracted angle is at 90 degrees.

Question 53

The greater the refractive index...?

Answer 53

the lower the critical angle

Question 54

State and explain the expression for TIR.

Answer 54

n1sin1 = n2sin2 n1sinC = n2sin90 n1sinC = n2 SinC = n2/n1

Question 55

By using TIR, how can we find the refractive index of a media?

Answer 55

Find the critical angle, know one of the refractive index and use formula.

Question 56

List the EM waves in order.

Answer 56

Radio, Microwave, Infrared, visible light, ultraviolet, x-rays, gamma rays.

Question 57

Give all info on radiowaves.

Answer 57

Check

Question 58

Give all info on Microwaves.

Answer 58

Check

Question 59

Give all info on visible light.

Answer 59

Check

Question 60

Give all info on ultraviolet.

Answer 60

Check

Question 61

Give all info on gamma rays.

Answer 61

Check

Question 62

Give all info on gamma rays.

Answer 62

Check

Question 63

If a wave is entering a medium of lower refractive index, where does it refract?

Answer 63

Wave speeds up, refract away from normal. Inverse proportion from n =c/v