6.1, 6.2 and 6.3 The Electromagnetic Spectrum/Light, Infrared, Microwaves and Radio Waves/Communications

Question 1

What do electromagnetic waves do?

Answer 1

Transfer energy from one place to another

Question 2

What does the amount of energy that electromagnetic waves transfer depend on?

Answer 2

The wavelength of the waves

Question 3

What is the order of the electromagnetic spectrum?

Answer 3

Radio waves 
Micro waves 
Infrared radiation 
Visible light 
Ultraviolet lights
X Ray 
Gamma ray

Question 4

How fast do all electromagnetic waves travel?

Answer 4

300 million m/s

Question 5

Describe the similarities and differences of the EM waves

Answer 5

Similarities:
Same wave speed
All travel through a vacuum

Differences:
Different wave lengths
Different frequencies

Question 6

How do we group the EM waves?

Answer 6

According to their wavelength

Question 7

Which type of rays have the shortest wavelength?

Answer 7

Gamma rays

Question 8

Which type of EM waves have the highest frequency?

Answer 8

Gamma rays

Question 9

What is the average wavelength of a gamma ray?

Answer 9

10 to the power of -15 m

Or

0.000000000000001

(14 0’s)

Question 10

Which type of EM waves have the longest wavelength?

Answer 10

Radio waves

Question 11

What type of EM waves have the lowest frequency?

Answer 11

Radio waves

Question 12

What is the average wave length of a radio wave?

Answer 12

10,000m

Question 13

What is the relationship between the frequency of an EM wave and the amount of energy it transfers?

Answer 13

The higher the frequency, the more energy it transfers

Question 14

Why are the wavelengths and frequencies at the boundaries of the different EM waves approximate?

Answer 14

The different parts of the spectrum are not precisely defined

Question 15

How do different surfaces react to the different wavelengths of the EM waves?

Answer 15

Different wavelengths of EM radiation are reflected, absorbed or transmitted differently by different substances and types of surface

Question 16

Which part of the EM spectrum transfers the most energy?

Answer 16

Gamma rays

Question 17

What are electromagnetic waves?

Answer 17

Electric and magnetic disturbances

Question 18

Where can we emit radio waves from?

Answer 18

An alternating voltage applied to an aerial emits radio waves with the same frequency as the alternating voltage. When the waves are received, they create an alternating current in the aerial with the same frequency as the radiation received

Question 19

Name 3 uses of radio waves

Answer 19

• TV
• radio
• mobile phone

Question 20

Name a danger of radio waves used in mobile phones

Answer 20

•radiation on the phone can cause damage to our brains

Question 21

What else gives off radio waves naturally?

Answer 21

Stars and lightning

Question 22

What can the frequencies of radio waves range between?

Answer 22

300,000Hz to 3 billionHz

Question 23

Where can micro waves be emitted from?

Answer 23

Satellites and pass through the atmosphere

Question 24

Name 2 uses of micro waves

Answer 24

• satellite TV

* mobile phones

Question 25

Name a danger of micro waves used in mobile phones

Answer 25

Radiation on phone could cause damage to our brains

Question 26

Which waves spread out more: radio or micro?

Answer 26

Radio waves

Question 27

Where is infrared radiation emitted?

Answer 27

All objects emit infrared radiation

Question 28

Name 3 uses of infrared radiation

Answer 28

* optical fibres * remote controls * infrared scanners/cameras

Question 29

Name a danger of infrared radiation

Answer 29

•absorbed by the skin so can be dangerous to skin cells if they are heated too much and can be destroyed

Question 30

What is the relationship between the heat of an object and the amount of infrared radiation it emits?

Answer 30

The hotter the object is, the more infrared radiation it emits

Question 31

Name 2 sources of visible light

Answer 31

* the sun | * ordinary lamps

Question 32

Name two uses of visible light

Answer 32

* lamps | * light bulbs

Question 33

Name 2 dangers of visible light

Answer 33

* sun can cause blindness | * sun burn can cause cancer

Question 34

Where is ultraviolet radiation emitted from?

Answer 34

Stars

Question 35

Name 3 uses of ultraviolet radiation

Answer 35

* to check bank notes * suntan * nail salon

Question 36

Name 2 dangers of ultraviolet radiation

Answer 36

* sun burn | * skin cancer

Question 37

Name 2 sources of x rays and gamma rays

Answer 37

* stars | * X-Ray machines

Question 38

Name 2 uses of X-rays and gamma rays

Answer 38

* airport security | * hospitals

Question 39

What EM waves are the most dangerous and why?

Answer 39

Gamma rays because they have the highest frequency

Question 40

Name a danger of X-rays and gamma rays

Answer 40

•causes cancer

Question 41

What do we see the different wavelengths of visible light as?

Answer 41

Different colours

Question 42

Which colour has the lowest wavelength?

Answer 42

Violet

Question 43

Which colour has the biggest wavelength?

Answer 43

Red

Question 44

Why is micro wave and radio wave radiation dangerous for us?

Answer 44

They penetrate our skin and are absorbed by body tissue, this can heat your internal organs and damage them

Question 45

What is the radio wave and microwave spectrum split into?

Answer 45

Different bands, decided by the different communication purposes

Question 46

What does a shorter wavelength mean for the amount of information it carries, their range and the amount they spread out?

Answer 46

The shorter the wavelength •the more information they carry •the shorter their range •the less they spread out

Question 47

What type of EM wave lets your phone transfer information to a local mobile phone mast?

Answer 47

Micro waves

Question 48

What are optical fibres and what are they used for?

Answer 48

Very thin glass fibres used to transmit signals carried by visible light or infrared radiation

Question 49

How does a signal travel down the optical fibre?

Answer 49

Total internal reflection

Question 50

Why are optical fibres useful in communications?

Answer 50

They carry much more information and are more secure than micro waves as they use visible light and infrared which both have shorter wavelengths