Answer: it will take 1000 guitar players for sound intensity level to be 100 dB
Step-by-step explanation:
Given that;
noise level of a single player = 70 dB
Intensity of one guitar will be;
SL= 10 × log(I/I₀)
where I₀ is hum threshold intensity = 10⁻¹² W/m²
I is intensity of sound produced by 1 guitar
SL is intensity level of one guitar
so we substitute
70 = 10 × log(I/10⁻¹²)
70/10 = log (I/10⁻¹²)
I = 10⁻¹² × 10⁷
I = 10⁻⁵ W/m²
now Suppose n guitars produce sound intensity of 100 dB, then intensity of n guitars (In) will be;
100 = 10 × log(In/10⁻¹²)
log(In/10⁻¹²) = 100/10
In = 10⁻¹² × 10¹⁰ = 10⁻² Wm²
we know that Now intensity of 1 guitar I = 10⁻⁵ W/m²
so Intensity of n guitars will be;
n × I = In
n = In / I
we substitute
n = 10⁻² Wm² / 10⁻⁵ W/m²
n = 1000
Therefore, it will take 1000 guitar players for sound intensity level to be 100 dB