Waves

Question 1

What do waves do?

Answer 1

Transfer energy from one place to another through oscillations without transfer of the medium

Question 2

Transverse or Longitudinal?

Answer 2

Transverse

Question 3

Transverse or Longitudinal?

Answer 3

Longitudinal

Question 4

Fill in the gaps

Answer 4

Question 5

Fill in the gaps

Answer 5

Question 6

What is amplitude and what is it measured in?

Answer 6

The maximum distance particles vibrate from rest position, measured in metres

Question 7

What is frequency and whats it measured in?

Answer 7

Number of waves per second in Hertz

Question 8

What is wavelength and whats it measured in?

Answer 8

Length of one whole wave, in metres

Question 9

What’s meant by time period and whats it measured in?

Answer 9

Time taken for a whole wave to pass a point in seconds

Question 10

In transverse waves, what’s the relationship between the oscillations and the direction of energy transfer?

Answer 10

Oscillations are perpendicular to the direction of energy transfer

Question 11

In longitudinal waves, what’s the relationship between the oscillations and the direction of energy transfer?

Answer 11

Oscillations are parallel to the direction of energy transfer

Question 12

Equation that links period and frequency:

Answer 12

period = 1/frequency

Question 13

Equation for frequency

Answer 13

frequency = number of waves / time

Question 14

Why are microwaves used for satellite communications?

Answer 14

They can pass through the atmosphere

Question 15

What are EM Waves?

Answer 15

Transverse waves that transfer energy from the source of the waves

Question 16

Name 2 properties of EM Waves

Answer 16

• Transverse
• Can travel through a vaccuum
• Transfer energy from one place to another

Question 17

What is 1 micro second in standard form?

Answer 17

1 x 10^-6

Question 18

Whats a nanosecond in standard form?

Answer 18

1 x 10^-9

Question 19

Whats a mega second in standard form?

Answer 19

1 x 10^6

Question 20

What’s a Giga second in standard form ?

Answer 20

1 x 10^9

Question 21

Between Radio waves and visible light which would wave could transfer more info and why?

Answer 21

Visible light because shorter wavelength waves can transfer more information

Question 22

What is meant by ionising radiation?

Answer 22

High energy waves that can cause atoms to become charged

Question 23

Why is ionising radiation dangerous for humans?

Answer 23

It can damage living cells

Question 24

What is the effect of high doses of ionising radiation on living cells?

Answer 24

It can kill the cell

Question 25

What is the effect of lower doses of ionising radiation on living cells?

Answer 25

Can cause mutations or cancerous growth

Question 26

What are X-Rays most commonly used for?

Answer 26

To form an image of your bones inside your body

Question 27

Why do X-Rays only produce an image of the bone?

Answer 27

Because they pass through skin and soft tissue and are stopped by bone

Question 28

What can high energy X-Rays and Gamma Rays be used for?

Answer 28

Treating cancer

Question 29

Which are better emitters and absorbers of IR Radiation, Light & Shiny surfaces or Dark and Matt Surfaces?

Answer 29

Dark and Matt

Question 30

What is meant by the angle of incidence?

Answer 30

The angle at which the wave hits the normal

Question 31

What is the relationship between the angle of incidence and reflection?

Answer 31

They are equal

Question 32

What is meant by refraction?

Answer 32

Light changes direction as it travels from one medium to another

Question 33

Why does refraction occur?

Answer 33

Because the speed of light is different in different materials

Question 34

What do lenses do?

Answer 34

Change the direction of light rays by refraction

Question 35

What do converging lenses do?

Answer 35

Make parallel rays converge to a focus

Question 36

What do diverging lenses do?

Answer 36

Make parallel rays spread out

Question 37

What is meant by principal focus?

Answer 37

The point where the rays appear to come from

Question 38

What is meant by the focal length?

Answer 38

The distance from the centre of the lens to the principle focus

Question 39

Are convex lenses converging or diverging?

Answer 39

Converging

Question 40

Are concave lenses converging or diverging?

Answer 40

Diverging

Question 41

What colours make yellow?

Answer 41

Red and Green

Question 42

What colours make Magenta?

Answer 42

Red and Blue

Question 43

What colours make cyan?

Answer 43

Green and Blue

Question 44

What colour will a yellow ball appear in green light?

Answer 44

Green

Question 45

Why does a blue ball appear black in red light?

Answer 45

Because there is no blue light for the ball to reflect so it’s absorbing all the light and it appears black

Question 46

What type of waves are sound waves?

Answer 46

Longitudinal pressure waves

Question 47

Which medium do sound waves travel fastest in?

Answer 47

Solid

Question 48

What are some uses of ultrasound?

Answer 48

• Echolocation • Pre-natal scanning • SONAR • Oceanic mapping • Breaking Kidney stones

Question 49

How is ultrasound used to treat kidney stones?

Answer 49

A powerful ultrasound wave causes the stone to vibrate and break into smaller parts.

Question 50

What is a black body?

Answer 50

A perfect absorber and radiator of heat

Question 51

True or False: The atmosphere is transparent to IR

Answer 51

False, its opaque