Dangers of the EM spectrum Flashcards
The higher the frequency…..
The more energy the radiation has and so the more harmful the radiation.
What does the effect of electromagnetic radiation depend on?
The frequency of the EM wave as frequency determines the energy of the wave.
How can microwaves affect human tissue?
Heat human body cells.
How does excessive exposure of microwaves heat human body cells?
Microwaves increase the vibrations of molecules (due to being similar) so heat things up. Certain frequencies are used in microwave ovens as they can heat water - so are dangerous to humans because most of our bodies are made up of water. Due to this, microwaves can heat human body cells.
Why do mobile phone signals use different frequencies of microwaves than those used in microwave ovens?
To prevent brain tumours and human cells heating.
How can infrared affect human tissue?
Causes skin burns.
How does excessive exposure of infrared cause skin burns?
Infrared also makes the surface molecules of any substance vibrate.
The skin absorbs infrared, which we feel as heat. Too much infrared radiation exposure can damage or destroy cells which causes skin burns.
How can ultraviolet radiation affect human tissue?
Cause skin cancer and damage eyes.
How does UV radiation cause sunburn?
Surface skin cells are damaged by absorbing too much UV rays in sunlight.
How does excessive exposure of UV radiation cause skin cancer?
Absorbing too much UV rays from sunlight cause skin burn, which can damage our cells DNA so causes cell mutations which is cancer.
How is UV radiation carried?
Through sunlight.
How does excessive exposure to UV radiation cause eye problems?
The UV in sunlight can damage our eyes -
Skiers, etc can suffer temporary ‘snow blindness’ because UV is reflected from the snow.
UV exposure over a long time can cause cataracts - reducing vision.
How does X - rays and Gamma rays affect human tissue?
Cause cell mutations and cancer.
How does excessive exposure of X - rays and Gamma rays cause cell mutations and cancer?
X and gamma rays are ionising radiation so cause cell mutations and changes in DNA that may kill cells causing tissue damage and cancer.
