Topic 5 Flashcards
Which are the most energetic and the most dangerous waves
The ones with the highest frequencies (shortest wavelengths) are the most energetic
Dangers of gamma rays and X-rays
Can cause mutations (changes) to the dna in the cells in the body
Could kill cells or cause cancer
Dangers of ultraviolet
UV in sunlight can damage skin cells, causing sunburn
Overtime exposure to UV can cause skin cancer
UV can also damage the eyes leading to eye conditions
Infrared dangers
Infrared radiation transfers thermal energy. Too much infrared radiation can cause skin burns
Dangers of microwaves
Heat water
So they can the water inside our bodies
Heating cells can damage or kill them
Use of gamma rays
To sterilise good and medical equipment
In scanners to detect cancer
To treat cancer
Use of x rays
To look inside objects including medical x-rays to look inside bodies
In airport security scanners, to see what people have in their luggage
Use of ultraviolet
To detect security marks made using special pens
Inside fluorescent lamps
To detect forged banknotes
To disinfect water
Use of visible light
Allows us to see, lights up rooms and streets, building and roads
Photography
Use of infrared
In cooking (by girls and toasters)
To make thermal images (images using heat) used by police and rescue services
In short range communications such as between laptops or other small computers
In remote controls for TVs and other appliances where the signal only has to travel short distances
To send information along optical fibres
In security systems such as burglar alarms to detect pills moving around
Used of microwaves
In mobile phones, and to communicate by satellite transmissions
For cooking (in microwave ovens)
Used of radio waves
Broadcasting radio and TV programmes
Communicating with ships, aeroplanes and satellites
Radiation is absorbed or emitted when
Electrons jump between energy levels
Electrons can only exist in atoms at certain
Well defined energy levels
What do the energy levels in atoms depend on
Depend on the atom and the electrons inside the atom can move between the shells or leave the atom completely
Electromagnetic radiation is emitted or absorbed by atoms based on wether
Energy is given out of taken in
Electrons move up energy levels when they
Absorb energy and they fall down to lower energy levels when they emit energy
Electrons move from a lower energy to a higher energy level when
The correct amount of energy is absorbed
Electromagnetic radiation is emitted when electrons
Fall down from a higher to a lower energy level
Where can energy also be emitted from?
The nucleus of unstable atoms
What do protons and neutrons also occupy
Energy levels in the nucleus in the same way tht electrons do in the atom
When energy changes occur in the nucleus
High energy gamma rays are emitted
Gamma-rays can be emitted over a large range of frequencies depending on
The energy levels within the nucleus
Explain the energy changes that occur within the electron levels of the atom
Electrons can move between energy levels if they absorb or emit electromagnetic radiation
When they absorb electromagnetic radiation they move up energy levels and when they emit electromagnetic radiation they move down energy levels
The energy of electromagnetic radiation that is emitted or absorbed has to match the
Difference between the energy levels that the electron is moving between
Which energy changes are greater the ones in the nucleus or this seen between electron energy levels
In the nucleus
Atoms have a nucleus containing
Protons and neutrons
What move around the nucleus of the atom
Electrons
Protons =
Electrons
+ charged =
- charges so no overall charge