P13 - Electromagnetic Waves 2️⃣✅ Flashcards
What are carrier waves?
Waves used to carry any type of signal
What is a contrast medium?
Am X-ray absorbing substance used to fill a body organ so the organ can be seen on a radiograph (X-ray)
What is the electromagnetic spectrum?
The continuous spectrum of electromagnetic waves
What is ionisation?
Any process in which atoms become charged
What are microwaves?
Electromagnetic waves between infared radiationa dn radio waves in the electromagnetic spectrum
What is optical fibre?
Thin glass fibre used to transmit light signals
What is radiation dose?
The ammount of ionising radiation a person recieves
What are radio waves?
Electromagnetic waves with wavelengths greater than 0.10m
What is ultraviolet radiation (UV)?
Electromagnetic waves between visivble light and X-rays in the electromagnetic spectrum
What is wave speed?
The distance travelled per second by a wave crest or trough
What is white light?
Light than includes all the colours of the spectrum
What is absorption?
The transfer of energy from teh wave to the medium - when something goes in but doesnt come out
What is transmission?
When something enters another mediunm and still comes out the other side - it isnt absorbed
What waves have ionising power on the electromagnetic spectrum?
UV, X-rays & Gamma rays have the ability to knock off electrons from atoms which can be dangerous in your cells, specifically DNA
Frequency of waves ________________ the electromagentic spectrum
increase up
Wavelength of waves ________________ the electromagnetic spectrum
decrease up
What is the equation for wavespeed?
V = f x λ
wavespeed = frequency x wavelength
What are the 4 ways heat is transferred?
- Coduction
- Convection
- Radiation
- Evapouration
What is black body radiation?
Black bodies are perfect absorbers & emitters of radiation thereofore black bodies neither relfect or transmit & all wavelengths are absorbed
What is the ionosphere?
A layer of ions in our atmosphere. Radiowaves are reflected by the ionosphere
What colour has the largest wavelength?
Red
What colour has the smallest wavelength?
Violet