P2 - Radiation and life Flashcards
List electromagnetic spectrum from longest waves to shortest waves.
Radio waves Microwaves Infrared radiation Visible light UV radiation X-rays Gamma radiation
What are photons?
Packets of energy that deliver different types of energy
What end of the electromagnetic spectrum has photons that carry the most energy.
Gamma photon
What is it called when photons with enough energy break molecules into ions
Ionisation
What two things does the intensity of EM radiation depend on?
- energy of the photons
- energy arriving every secondt
What happens to the intensity of radiation the further away the detector is from the source?
It decreases
What is the speed of light?
300 000 km/s
What is a light year?
How far light travels in a year
Why is a light year 1x 10 tpo 13 km?
300 000 x 60s x 60min x 24h x 365days = 9.46 x 10 tpo 12 km
How do scientist study stars?
They look at the radiation coming of them.
Ionisation of a molecule can start a chemical reaction involving that molecule which can result in …
Cancer due to the mutated cells
X-rays are used to make shadow pictures of people’s bones or their luggage. They use x-rays for this because…
They are absorbed my dense materials.
What are the possible risks of harm from science based technology
Skin cancer
Burns
Radiation
If changes in factor always result in changes in an outcome. There is always a …
Correlation
Why are people’s perception about risk unrealistic?
- fear the unknown
- minimise the risk for things they enjoy
What are the two things are considered when making a decision about risk?
- the chance of it happening
- it’s consequences of it happening
What absorbs ultra violet radiation?
- sunscreen
- clothing
- the ozone layer
Microwave radiation heat food?causes water molecules to
causes water molecules to to transfer energy from microwave photons to heat.
The warmed earth emits infrared radiation. Where does it go?
Some is absorbed by greenhouse gasses in the atmosphere, heating it up.
If the number of bytes of information transmitted increase, what happened to the quality of the sound or imitate recieved?
Increase
List electromagnetic spectrum from highest frequency to lowest.
Gamma radiation X-rays Ultraviolet Visible light Infrared radiation Microwaves Radio waves
Why are some people worried about the health risks of microwaves?
-The heating affect of microwaves(although very small)
How are the risks of microwaves measured?
Comparing cancer rates of a large sample size in people who do an do not use phones.
How does UVC get through the ozone layer?
It is a torn get intensity and causes a chemical change to molecules in the ozone layer.
Describe the greenhouse affect
Earth warms up when it absorbs radiation from the sun.
IM radiation emotes from earth = cools down.
Some will pass into space.
Some reflected by the clouds and absorbed by pollutants.
= earth warms up.
