Electromagnetic Spectrum Flashcards
Electromagnetic waves
Transverse waves, transferring energy
-travel through vacuums at 3x10^8 m/s
Electromagnetic spectrum
High frequency, short wavelength
Gamma rays
X rays
UV
Visible light
Infrared
Microwaves
Radio waves
Lowest frequency, largest wavelength
Gamma rays
Produced during nuclear decay of a nucleus of a radioactive isotope
Uses
-sterilisation
-medical imaging
-radiotherapy
X rays
Produced by the rapid deceleration of free electrons due to changes in the organisation of electrons orbiting the nucleus
Uses
-medical imaging
-medical treatment
-airport security
UV
Hazards
-sunburn
-skin cancer
-blindness
Uses
-disinfectant
-energy saving light bulbs
-security ink
Infrared (thermal radiation)
Uses
-electrical heaters
-cookers
-fibre optic communication
-remote control
-thermal imaging
Microwaves
Uses
-cooking food
-satellite communication
-bluetooth (pass easily through earths atmosphere)
Radio waves
Produced by a man-made oscillations in electrical circuits in a wire (AC)
Uses
-radio and TV signals
-radar
Radio wave production
1) at the transmitter, an electrical input signal causes electrons to oscillate up and down the antenna
2) this leads to production of radio waves which travel from the transmitter to receiver
3) at the receiving antenna, energy from the incident radio waves causes electrons to oscillate
4) this is detected as an electrical signal which is what carries the radio/TV broadcast to the receiver
Visible light
Uses
-human sight
-lasers
-fibre optic communication