Chapter 13 - The Electromagnetic Spectrum

Question 1

What type of wave are the waves in the electromagnetic spectrum?

Answer 1

Transverse

Question 2

Electromagnetic waves definition

Answer 2

They are electric and magnetic disturbances that transfer energy (NOT MATTER)

Question 3

Name the order of the electromagnetic spectrum starting from the lowest wavelength

Answer 3

Radio
Microwave
Infrared
Visible
Ultraviolet
X-ray
Gamma ray

Red Meat Is Very Useful Xcept Goats

Question 4

What wavelengths can the human eye see between?

Answer 4

350 nm and 650 nm

Question 5

All electromagnetic waves travel at ___________ in a vacuum

Answer 5

All electromagnetic waves travel at 3x10^8 m/s in a vacuum

Question 6

What is the equation linking wave speed, frequency and wavelength?

Answer 6

Wave speed = Frequency x Wavelength

Question 7

When you combine all the colours of the spectrum you get the colour __________

Answer 7

white

Question 8

Violet has the ________ wavelength and red with the ____________ wavelength

Answer 8

shortest, longest

Question 9

Uses of light (4 uses)

Answer 9

Torches
Cameras
Endoscopes
Optical fibres

Question 10

True or false? All objects emit infrared radiation

Answer 10

True

Question 11

Uses of infrared radiation (4 uses, think of red light!)

Answer 11

Optical fibres
Remote controls
Thermal imaging
Ovens

Question 12

Uses of microwaves (3 uses)

Answer 12

Microwave oven
Mobile phones
Satellite communication

Question 13

Uses of radio waves (3 uses)

Answer 13

Radio
Bluetooth
Remote Control Car

Question 14

Dangers of infrared (2 dangers)

Answer 14

Skin burns
Damage to eyesight

Question 15

Dangers of microwaves and radio waves

Answer 15

Heating internal body parts

Question 16

Waves can transfer _______ and __________

Answer 16

energy, information

Question 17

Carrier waves are waves that carry ____________. They do this by ______________________________

Answer 17

information, varying their amplitude

Question 18

EM waves change properties based on their __________ and ___________________

Answer 18

frequency, wavelength

Question 19

Shorter _________ (higher ________) mean more waves can arrive at the same time so more info can be transferred

Answer 19

wavelengths, frequency

Question 20

Downside to shorter wavelengths carrying information

Answer 20

Their range is less, due to increased absorption by the atmosphere (which means they spread out less)

Question 21

Radio waves have uses depending on their _________

Answer 21

wavelength

Question 22

What device converts sound to an electrical signal?

Answer 22

A microphone

Question 23

Are the brains of children or adults affected by mobile phone use?

Answer 23

-> Mobile phones use microwave signals
-> Children have thinner skulls than adults
-> Their brains may be more affected by mobile phone radiation

Question 24

Which 2 parts of the EM spectrum do optical fibres use?

Answer 24

-> transparent fibres that are used to transmit signals by IR and visible light
-> these can transfer more information because light has a shorter wavelength than radio waves
-> more secure because signal is contained in fibre not in air

Question 25

Uses of UV (think of escape rooms)

Answer 25

Security:
banknotes (uv markings)
security pens

Question 26

Dangers of UV (3 dangers)

Answer 26

• Sunburn (which can lead to premature aging of the skin)
• Increases chance of skin cancer
• Can cause damage to eyes (potentially blindness

Question 27

Gamma rays uses (2 uses)

Answer 27

• Killing harmful bacteria in food or on surgical equipment
• Cancer treatment

Question 28

Use of x-rays

Answer 28

Medical imaging

Question 29

What is ionisation?
What is its cause?
What happens if ionisation happens to living cells?

Answer 29

• When an atom gains or loses an electron
• Cause = x rays or gamma rays passing through a substance
• If ionisation happens to living cells it can damage cells and potentially cause cancer

Question 30

What do people who work with ionising radiation wear?

Answer 30

A safety film badge