Chapter 4

Question 1

What is wave motion?

Answer 1

The transfer of energy without the transfer of matter

Question 2

What are transverse waves?

Answer 2

Particles moving at right angles to the direction that the wave travels.

Question 3

What are examples of transverse waves?

Answer 3

Ocean waves, mexican wave, seismic s-waves, electromagnetic waves

Question 4

https://docs.google.com/presentation/d/1n4DHwJrw0CehB1twyPXwSw50Zs6rFKezbWFqK-wh4lc/edit#slide=id.g125b48e154a_0_159

Answer 4

Do it!!

Question 5

What are longitudinal waves?

Answer 5

Particles moving back and forth in the same direction that the wave travels.

Question 6

What are examples of longitudinal waves?

Answer 6

Sound waves, seismic p-waves

Question 7

What is frequency?

Answer 7

The number of complete waves passing a point in one second (measured in hertz, Hz)

Question 8

What is wavelength?

Answer 8

The distance between two crests or two troughs, or between two compressions or two rarefactions

Question 9

What is amplitude?

Answer 9

The maximum distance the wave extends upwards from its middle position.

Question 10

What is the wave equation?

Answer 10

v = fλ

Question 11

What is v?

Answer 11

The speed the wave travels (m/s)

Question 12

What is f?

Answer 12

The frequency of the wave (Hz)

Question 13

What is 𝛌

Answer 13

The wavelength (m)

Question 14

What is white light?

Answer 14

All the colours of the visible spectrum

Question 15

Why do white objects appear white?

Answer 15

They reflect back all the visible wavelengths of light that shine on them on to our eyes - so the light still looks white to us.

Question 16

Why do coloured objects appear coloured?

Answer 16

They reflect back only some of the wavelengths to our eyes; the rest they absorb.

Question 17

What is an analogue signal?

Answer 17

Where the voltage of the signal is determined by the speaker’s voice.

Question 18

What is an digital signal?

Answer 18

A signal that only takes a one or a zero

Question 19

How does a mobile phone network work?

Answer 19

Transmits microwaves of your voice to base stations, then

Question 20

What is a router?

Answer 20

A device that manages the connection between your computer and internet server.

Question 21

What is ultraviolet light?

Answer 21

Light with a higher frequency than violet light. Sunlight contains UV light

Question 22

What light does the sun emit?

Answer 22

Infrared, visible and UV

Question 23

What are the types of UV light?

Answer 23

UV-A, UV-B, UV-C

Question 24

What are the benefits of UV light?

Answer 24

Needed for Vitamin D, counterfeiting prevention

Question 25

What are the harms of UV light?

Answer 25

High energy UV radiation can cause skin cancer and cataracts

Question 26

What are X-rays used for?

Answer 26

Investigating the structure of objects with their strong penetrating power

Question 27

What can X-rays harm?

Answer 27

Damage cells and DNA

Question 28

What are the benefits of X-rays?

Answer 28

Scanning body parts, radiotherapy and airport security

Question 29

What are the harms of X-rays?

Answer 29

Can damage cells and cause mutations

Question 30

Description of gamma rays

Answer 30

Carry high amounts of energy, and are said to be ionising (Can free electrons from their atoms)

Question 31

What are the benefits of gamma rays?

Answer 31

Radiotherapy, sterilisation of medical equipment and food

Question 32

What are the harms of gamma rays?

Answer 32

Can damage cells and lead to mutations