The noise from a power mower was measured at 106 db. the noise level at a rock concert was measured at 115 db. find the ratio of the intensity of the rock music to that of the power mower. (round your answer to the nearest whole number.)

= 8

Explanation:

noise from power mower = 106 dB

noise from rock concert = 115 dB

we would be applying the formula for the decibel level of sound to get the intensities.

(B) = 10 log \frac{I}{I₀}

I = intensity of sound

I₀= reference intensity = 10^{-12} W/m^{2}

106 = 10 log \frac{I}{10^{-12}}

10.6 =  log \frac{I}{10^{-12}}

10^{10.6} = \frac{I}{10^{-12}}

I = 10^{10.6} x 10^{-12}

I of power mower = 0.0398 W/m^{2}

115 = 10 log \frac{I}{10^{-12}}

11.5 =  log \frac{I}{10^{-12}}

10^{11.5} = \frac{I}{10^{-12}}

I = 10^{11.5}  x 10^{-12}

I of rock music = 0.316 W/m^{2}

now the ratio of the intensity of the rock music to the power mower

= \frac{0.316}{0.0398}

= 8

where is the circuit diagram ?

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.