Electromagnetic waves Flashcards
1
Q
What are the characteristics of electromagnetic waves
A
- Made up of oscillating electric and magnetic fields
- Transverse waves, so their electric and magnetic waves oscillate perpendicularly to the direction of propagation
- Do not carry electric charges
- Transfer energy
- Undergo reflection and refraction
- Frequency does not change in a different medium
- Speed of 3.0x10^8 in vacuum
- Wave speed equation applied to all electromagnetic waves
2
Q
Name the electromagnetic spectrum from lowest frequency
A
- Radio waves
- Microwaves
- Infrared radiation
- Visible light (Red>Violet)
- UV radiation
- X-rays
- Gamma rays
2
Q
Which wave has the highest frequency
A
Gamma rays
3
Q
Which wave has the lowest wavelength
A
Gamma rays
3
Q
Which wave has the highest wavelength
A
Radio waves
4
Q
Which colour of visible light has the lowest wavelength
A
Violet
5
Q
Which colour of visible light has the highest frequency
A
Violet
6
Q
What are radio waves used for
A
- Television and radio communication
- Radio telescopes
- Radio Frequency Identification tags for library books
7
Q
What are microwaves used for
A
- Microwave oven
- WiFi signals
- Mobile phone communication
- GPS and radar
- Satellite communication
7
Q
What is visible light used for
A
- Photography
- Optical fibres in medicine and telecommunication
8
Q
What are some hazardous effects of infrared radiation
A
Heating effect
9
Q
What are some hazardous effects of microwaves
A
Heating effect
9
Q
What is infrared radiation used for
A
- Remote control
- Intruder alarm
- Thermal imaging
- Camera autofocusing
9
Q
What is UV radiation used for
A
- Sterilisation of medical equipment
- Disinfectant of water
- Sunbed for artificial tanning
- Check for counterfeit bank notes
9
Q
What are some hazardous effects of UV radiation
A
- Prolonged exposure can lead to sunburns, premature ageing and increased risk of skin cancer
- UV radiation can be ionising
