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Please help Preliminary Dot Point (1 Viewer)
- Thread starter Praer
- Start date
qwerty44
Member
- Joined
- Oct 12, 2011
- Messages
- 557
- Gender
- Male
- HSC
- 2013
Just do that. Just talk abou a modern use for most of the electromagnetic spectrum.
i.e. Light in fibre optics, radio waves in radios
D), microwaves in.....get the idea?
theind1996
Active Member
Not sure if this is useful at all, but from my Year 10 Science knowledge:
Radiowaves: Transmits radio and TV signals, radar in air traffic control.
Microwaves: Used in cooking and radar speed guns used by police.
Infrared Waves: Given off by hot objects, used to take temperature pictures and find people in collapsed buildings.
Visible Light: Seeing and eyesight, photosynthesis and photography.
UV Rays: Used in Fluorescent lamps and sterilisation.
X Rays: Radiography, treating cancer, finding faults in metals and examining crystals.
Gamma Rays: Used to measure thickness of metals, sterilize medical equipment.
Distance:
o attenuation (when waves decrease in strength over long distances, inverse square law), effects communication because the signal could become much more weak and be less effective for the receiver.
o To reduce this, they need to be sent out at greater strength or have boosters/ repeater stations
Congestion:
o as more and more people access the limited range of frequencies, they become more congested and interference may occur
o To reduce this, new method of technology needed to be created which utilise other types of the spectrum like infra-red and light waves as they are in enclosed systems where penetration and attenuation are not problems
Health:
o Microwaves used in mobiles are controversial as it is unknown if the frequency is high enough to alter human cells
Radiowaves: Transmits radio and TV signals, radar in air traffic control.
Microwaves: Used in cooking and radar speed guns used by police.
Infrared Waves: Given off by hot objects, used to take temperature pictures and find people in collapsed buildings.
Visible Light: Seeing and eyesight, photosynthesis and photography.
UV Rays: Used in Fluorescent lamps and sterilisation.
X Rays: Radiography, treating cancer, finding faults in metals and examining crystals.
Gamma Rays: Used to measure thickness of metals, sterilize medical equipment.
Distance:
o attenuation (when waves decrease in strength over long distances, inverse square law), effects communication because the signal could become much more weak and be less effective for the receiver.
o To reduce this, they need to be sent out at greater strength or have boosters/ repeater stations
Congestion:
o as more and more people access the limited range of frequencies, they become more congested and interference may occur
o To reduce this, new method of technology needed to be created which utilise other types of the spectrum like infra-red and light waves as they are in enclosed systems where penetration and attenuation are not problems
Health:
o Microwaves used in mobiles are controversial as it is unknown if the frequency is high enough to alter human cells