Page 88 - sss_Neat
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= 10 log
0
60 dB = 10 log
10 −12
60
= log
10 10 −12
6
= 60 dB 10 = 10 −12
2
−6
= 10 W/m
= 50 m
⋯
= 2
4
2
−6
10 W/m =
4(3,14)(50) 2
2
−6
10 W/m =
3,14×10 4
2
4
−6
= 10 log = (10 W/m )3,14 × 10
0
−2
= 3,14 × 10 watt
=
4 2 3,14 × 10 −2 watt
