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Sliva [168]
3 years ago
10

Two friends whisper at a volume of 20 decibels. Later, they converse at a volume of 40 decibels.

Physics
2 answers:
ruslelena [56]3 years ago
6 0

Answer:

Explanation:

The sound intensity is given by:

I (dB) = 10 log(I/Io)

Where I is the intensity in W/m²

Io = 1.0 × 10⁻¹² W/m²

40 dB = 10 log\frac{I_2}{I_o} \Rightarrow I_2 = 10^4 \times 1.0 \times 10^{-12}W/m^2 = 10^{-8}W/m^2

20 dB = 10 log\frac{I_1}{I_o} \Rightarrow I_1 = 10^2 \times 1.0 \times 10^{-12}W/m^2 = 10^{-10}W/m^2

\frac{I_2}{I_1} = \frac{10^{-8}W/m^2}{10^{-10}W/m^2}=100

Thus, the conversation would have 100 times greater than the whisper.

Yuki888 [10]3 years ago
4 0
40 dB is 20 dB more power than 20 dB is. 20 dB more means 100 times as much.
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Answer:

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(c)

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E = P/t................ Equation 4

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