Quiz quiz swap
C/W 1st October 2011
Recap - Effects of ionising radiationKeywords: gamma rays radioactive X-rays radiographer
Objectives:Must – Understand the risk of using x-rays and gamma raysShould – understand the precautions you need to take with x-rays and gamma rays.Could – Understand risk, and perceived risk
Electromagnetic Spectrum
Radio
Micro
Infra-Red
Light
Ultra-V
iolet
X rays
Gam
ma
Wavelength () increases
Can you think of a phrase that would help you remember this order? Gate X Usually Lets In Most Radiation
High frequency
Short wavelength
High energy
Most penetrating
High frequency
Short wavelength
High energy
Most penetrating
Low frequency
Long wavelength
Low energy
Least penetrating
Low frequency
Long wavelength
Low energy
Least penetratingx
There is radiation around us a lot of the time......Is this a problem?
CT scan (computer tomography) (drawing a map of your insides!) This uses x-raysWhat are the problems?What are the benefits?Is it worth it?
C/W 2nd November 2011
Microwaves Keywords: absorb microwave sample bias
Objectives:Must – Understand the heating effects of radiation can damage cellsShould – Know what microwaves can be used for. Could – Understand how risks can be assessed.
Microwaves transfer energy when absorbed by water, They transfer less energy than x-ray or gamma rays.
They still heat though because:1)They are very
intense2)The radiation is
absorbed for a long time.
HHo
We saw last week we can think of light as little packets of energy called photons.......
How microwave works clip
Mobile phones also use microwaves to send information
•These don’t heat your head so much, as they are less intense •There is no clear link yet between mobile phone use and cancer
Why are sun beds going to be banned?
C/W 2nd November 2011
Microwaves Keywords: absorb microwave sample bias
Objectives:Must – Understand the heating effects of radiation can damage cellsShould – Know what microwaves can be used for. Could – Understand how risks can be assessed.