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AttachmentT_C
<br />clear .ie�rs•--.,i g.uag tic energy.' In
<br />$'�iSL•:-' :t IS L�'^..•SA to have a ..._3: Lliti. .�,.s..►�. � about G:�.�•+-" Gr'•• � ►
<br />+t.... , r frequencies e- en"._ `
<br />wireless C.^.,=.:�.'.:i:.'::i:iOaS SYS.-.errs use lower ai _.?+Ll .....:..5 and lower energy levels Tj"' 3.~
<br />assoc:a:zd with =any other tyTcs of
<br />•
<br />Elec=o,::--azmetic waves have three. properties wb..ich ere: -aim. the': character. and, tiuS
<br />potential health effects. The first is fre�.:ency, which is the rate at which el=ti :gr_e`io craves
<br />pass. a f : ed point, or the rate at which waves are ge=razeed. Long" waves have a lower
<br />f:-ecue cy and sharer waves have a higher L-- ncv. F-... ,..,,.v is measured in cycles c
<br />wend, units called her after the C_ scientist who f ds.ove:rd radio waves (60
<br />Irz = 60 cy clesi se end) .
<br />The se r.d prop.: � is a:=:p Irelative •e energy et and � n :^ode, which is a :a• v rL,.:s•.:. of a wave's G..._, ev,. is
<br />related to a frequency. n_erally, waves with shorter wavel: gths chi_zher fr:rt:e:.^i:s)
<br />require generate, • T, • T
<br />carry tror_ energy for the same ar�iiaid.., ._�..i.:_ nor_ e...,.ro to g_ at, and this, car.
<br />wansL : =ore a=rgy when 'absorbed. Two waves with the sae wavelength can have different
<br />anaplirzcies based u cnhow much energy is put into each wave's produc:icn.
<br />1 energy as a
<br />The thirdthird property is the power density, which is a measure of a wave's rota.e...._-,
<br />fano:icn of its di5� fro= its source. it en a wave radiates away fro= its sourze, lire: a
<br />rinei: in a noel. thewave neethe ve way. When a radio wave is
<br />Ics_.s a .a::.._. it o s a
<br />broad rest, it loses energy according to the "inverse -square principle. In its sir Diest for , the
<br />principle says that every tom: you double the dim= fro= an e ri^.gig source, the power
<br />dersi.: decreases by a fac:or of four. Thus, a power level r ea *e originally at ten fet would
<br />rheas•::: one-fourth at 20 feet, one -sir a: 40 feet, and one stay -fourth at 80 feet.
<br />�'} ••,,,�. .:; el -tic �,� ---,
<br />in !'igL 9, rat,�f_,,. w QtaZ6��:..rr.. .ram l�l....s a sp.=ri Wl�i of frequencies lv�tz.1+ng
<br />f•Z"o= a few r` with wavelengts of over I„CCO k.loaettrs u7 to bLalo and billions of En with
<br />wavelezz s =uch s—L.lall-- tr.an -'Otis. Radio waves, located on the lower d of the S:.. c.-r a,
<br />have diszi=:: "wave i •" •- n^ '' e:leate at r_:.stivei low energy levels.
<br />-I.ic_ c:._.. _-:sues. a....:.� beg y .�-..,.
<br />Microwaves, L±are.-, visible. and ultraviolet found towards the middl.e of the s c --=.,
<br />ex ibit c:s.-ac:e:is-ics of both waves and particles. X-rays and ea=.=.a rays, at the high end of
<br />the y sp='•� �.,., distinct " T ie• " energies.
<br />frequency ,. --,:.' have j t;a.. Lc._ his_ characteristics and �:. _.... .s.
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<br />Figure 9
<br />LOCATION OF RADIOFi= EQUENCY RADIATION ON ELECTROMAGNETIC SPECTRUM
<br />Frequency/Hz
<br />1c
<br />is
<br />iti,."'.tAa ICN
<br />PA.:c I Lit C+PCSnl1V_ ISFR.& E
<br />1b'
<br />1V -
<br />VISIBLE l L'RA
<br />L'a%% vlcl: X-RAYS
<br />G.w A
<br />RAYS
<br />30
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