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3 years ago

7

You are using a hand-held sound level meter to measure the intensity level of the roars produced by a lion prowling in the high

grass. To decrease the measured sound intensity level by 36.2 dB requires the lion move away from you until its distance from you has increased by what factor? g

1 answer:

lions [1.4K]3 years ago

8 0

Answer:

64.57

Explanation:

We are given that

For decreasing measured sound intensity level=36.2 dB

We have to find the factor by which the distance increase.

Let initial distance=x

Final distance=x'

According to question

$36.2=10log(\frac{x'^2}{x^2})$

$36.2=10log(\frac{x'}{x})^2$

$36.2=10\times 2log\frac{x'}{x}$

$log\frac{x'}{x}=\frac{36.2}{20}=1.81$

$\frac{x'}{x}=10^{1.81}$

$x'=10^{1.81}x=64.57x$

Hence, the distance is increases by factor of 64.57

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