P12 Waves

Question 1

What are the properties of longitudinal waves

Answer 1

Show areas of compression and rarefaction

Directions of vibrations are parallel to direction of wave

Question 2

Properties of transverse waves

Answer 2

Has the vibrations perpendicular to direction of flow

Question 3

What is the amplitude of a wave

Answer 3

Maximum displacement of a point on a wave away from it’s undisturbed position

Question 4

What is the wavelength of a wave

Answer 4

Distance from a point on one wave to the equivalent point on the adjacent wave

Question 5

What is the frequency of a wave

Answer 5

Number of waves passing a point each second

Question 6

What is the equation for period

Answer 6

T = 1/f
Period = 1/ frequency

Question 7

Wave speed equation

Answer 7

V = f x λ
Speed = frequency x wavelength

Question 8

What happens if a light wave hits a boundary along the normal

Answer 8

It slows down but is not refracted

Question 9

What happens if a light wave hits a boundary at an angle

Answer 9

The wave slows down and changes direction - it refracts

Question 10

How to construct a ray diagram

Answer 10

1.Draw boundary and normal ( at 90° to boundary )
2. Draw incident ray that meets normal at the boundary ( angle between normal and incident is the angle of incidence )
3. Draw refracred ray on other side of boundary.
If material is optically denser than first: refracted ray bends towards the normal ( angle between normal and refraction is smaller than incidence )
If material is less optically dense: angle of refraction is larger than angle of incidence

Question 11

How do sound waves actually make noise

Answer 11

They vibrate through solids causing vibrations

Question 12

What is the range of normal human hearing

Answer 12

20Hz - 20kHz

Question 13

What are ultrasound waves

Answer 13

They have a frequency higher than human hearing

They can be used for medical imaging and industrial imaging

Question 14

How are ultrasound waves used for imaging

Answer 14

They are partially reflected when they meet a boundary between 2 media. The time taken for reflections to meet detector can be used to determine how far away the boundary is

Question 15

What 2 waves do earthquakes produce and how are they different

Answer 15

P - waves: longitudinal, travel through solids and liquids

S - waves: transverse, cannot travel through a liquid

Question 16

What is echo sounding

Answer 16

Using high frequency sound waves to detect objects in deep water and measure water depth

Question 17

What is the speed of light

Answer 17

300,000,000 m/s

Question 18

How does the human ear hear sound

Answer 18

Sound waves reach you ear drum and cause it to vibrate
The bibrations are passed through bones called ossicles, through the semicircular canal and to the cochlea
The cochlea turns the vibrations into electrical signals which get sent to your brain

Question 19

How is human hearing limited

Answer 19

Limited by the sound and shape of the ear drum as well as the structure of all parts of the esr that vibrate to transfer the energy from the sound wave