−6 1 × 10 W/m 2 = 10 log 0 1×10 −6 W/m 2 = 10 log 10 −12 W/m 2 = 100 buah mesin = 10 log 10 6 −6 = 1 × 10 W/m 2 = 10 (6) = 60 dB 100 =? = + 10 log 1 = 60 dB + 10 log 100 = 60 dB + 10(2) = 10 log = 60 dB + 20 = 80 dB 0 80 dB. = + 10 log 1