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silly question , electro magnetic waves

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mihir08

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When u radiate a high power EM wave (several KW) as used in radars , do they have the same energy when they get radiated in free space , i mean i never heard that some one coming in front of antenna getting hurt .
and one more
one of prof. said that micro waves are called " micro waves " because in free space their energy is in micro watts ,, is that true or is it because of their wavelength .
 

betwixt

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Micro-waves are called that because of the size of the waves, not because of their power. Think in terms of 'long wave', 'medium wave', 'short waves' and so on as the wavelengths have shorter lengths, microwaves are just extremely short waves.

Radar is extremely dangerous! Peak power is often several KW although necessarily for very short bursts so averaged over time the amount may appear quite small. Radar also directs the signal at different angles which also reduces the power per unit area. Most Radar systems will still make fluorescent tubes flash at a range of several hundred metres so do not underestimate the amount of energy they push out.

Brian.
 
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pstuckey

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The idea for the microwave oven was developed after a RADAR engineer noticed that a candy bar in his pocket would melt when he stood in front of a high power RADAR antenna.

Because of that there are safety regulations not only for RADAR, but cell phones and other wireless devices.
 

tpetar

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i mean i never heard that some one coming in front of antenna getting hurt .

Of course you didnt hear because they are rip, no one has lived to tell that he stood in front of the radar. Often radar personel in military have stronger food for lunch, with more milk and yogurt, and this huge energy can cause some problems on reproductive organs. Stronger losing of hair and nausea is first indicator of receiving high dose of energy. Its strongly prohibited for personel to stand in front or in in height of radar antena or close to it. ;-)

Russian S-300P have 350 kW to 1.23 MW signal strength. I think that S-400 can kill bird in sky just with radio wave, and cause very bad malfunction on airplane, just with radio waves on closer distance, and if someone from crew press red button all from sky will fall down maybe even stars.
 
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