Invisible Waves 9

Question 1

What is a wave?

Answer 1

a transfer of energy that spreads through a medium from the disturbance location, usually as vibrations in the medium

Question 2

What is a transverse wave?

Answer 2

a wave that consists of a disturbance occurring perpendicular to the equilibrium

Question 3

What is a longitudinal wave?

Answer 3

A wave that consists of a disturbance occurring parallel to the equilibrium

Question 4

What is a pulse wave?

Answer 4

A wave that is caused by a single disturbance

Question 5

What is a periodic wave?

Answer 5

A wave that is caused by a continuous and repetitive disturbance

Question 6

What is a period?

Answer 6

The duration of a single vibration

Question 7

What is sound?

Answer 7

A longitudinal wave travelling through a medium which can be detected by the ear

Question 8

What is pitch?

Answer 8

The frequency of a sound wave

Question 9

What is an electromagnetic wave?

Answer 9

A wave consisting of a vibrating electric field which causes a vibrating magnetic field

Question 10

What is light?

Answer 10

Electromagnetic waves that can be detected by the eye

Question 11

What is diffuse reflection?

Answer 11

The reflection of light from a surface that scatters the incident rays

Question 12

What is specular reflection?

Answer 12

The reflection of light from a surface so that the incident ray is reflected at the same angle

Question 13

What is refraction?

Answer 13

The change in direction of a wave passing from one medium to another one where it travels at a different speed

Question 14

What is this?

Answer 14

Diffuse reflection

Question 15

What is this?

Answer 15

Specular reflection

Question 16

What happens when a pulse wave is reflected?

Answer 16

It goes back and forth until it dies out

Question 17

Describe longitudinal wave characteristics

Answer 17

• sounds
• parallel
• rarefactions & compressions
• needs medium

Question 18

Describe transverse wave characteristics

Answer 18

• Electromagnetic radiation
• Light
• perpendicular
• troughs and peaks
• doesn’t need medium

Question 19

Describe the equation triangle for velocity, wavelength, and frequency

Answer 19

V

λ | ƒ

Question 20

Describe the equation triangle for velocity, wavelength, and time (period)

Answer 20

λ

V | t

Question 21

What is frequency measured in?

Answer 21

Hertz (Hz)

Question 22

What is velocity measured in?

Answer 22

m/s

Question 23

What is wavelength measured in?

Answer 23

metres (m)

Question 24

What is time measured in?

Answer 24

seconds (s)

Question 25

The bigger the amplitude the…

Answer 25

louder something is

Question 26

The higher the frequency the…

Answer 26

higher the pitch

Question 27

What does the speed of sound depend on?

Answer 27

The medium it's going through

Question 28

Does sound travel faster through air or a solid?

Answer 28

solid

Question 29

What is ultrasound?

Answer 29

sound above 20,000Hz

Question 30

Describe sound in terms of particles

Answer 30

When something vibrates, it hits the particles next to it causing them to vibrate, which then cause the particles next to them to vibrate, and so on until it dies out.

Question 31

Order electromagnetic radiation from highest to lowest frequency

Answer 31

gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, radio waves

Question 32

What does the visible spectrum wavelength range from?

Answer 32

700nm (red) to 400nm (violet)

Question 33

Describe the characteristics of AM radio signals

Answer 33

* can get static * vary amplitude based on message being sent * frequency stays the same * long wavelength * can bend

Question 34

Describe the characteristics of FM radio signals

Answer 34

* can't get static * vary frequency based on message being sent * amplitude stays the same * short (3m) wavelength * can't bend

Question 35

What is this?

Answer 35

total internal reflection

Question 36

When does total internal reflection happen?

Answer 36

When the angle of incidence is bigger than the critical ange

Question 37

What is the critical angle?

Answer 37

The angle of incidence when the angle of refraction is at 90 degrees

Question 38

How do you see colour?

Answer 38

objects absorb all visible light except they reflect the colour that they are back into your eye

Question 39

What is the equation triangle for speed, time and distance

Answer 39

d s | t

Question 40

What is this?

Answer 40

Virtual image

Question 41

What is this?

Answer 41

Real image

Question 42

What is the difference between a real and virtual image?

Answer 42

Real images * can be projected onto a screen * distance between image and lens is always closer than the lens and the object Virtual Image: * Cannot be projected onto a screen