Answer:
The distance from harvest mouse to the leaf is 4.74 m.
Explanation:
Given that,
Intensity = -10 dB
Distance = 1.5 m
We need to calculate the power of intensity
Using formula of power of intensity
[tex]P=I_{0}A[/tex]
[tex]P=I_{0}\times4\pi r^2[/tex]
Put the value into the formula
[tex]P=1.0\times10^{-12}\times4\pi\times(1.5)^2[/tex]
[tex]P=28.27\times10^{-12}\ W/m^2[/tex]
We need to calculate the minimum intensity level
Using formula of minimum intensity
[tex]I=10\log_{10}(\dfrac{I}{I_{0}})[/tex]
[tex]-10=10\log_{10}(\dfrac{I}{I_{0}})[/tex]
[tex]\log_{10}\dfrac{I}{I_{0}}=-1[/tex]
[tex]I=10^{-1}\times(1.0\times10^{-12})[/tex]
[tex]I=1\times10^{-13}\ W/m[/tex]
We need to calculate the area
Using formula of intensity
[tex]I=\dfrac{P}{A}[/tex]
[tex]A=\dfrac{P}{I}[/tex]
Put the value into the formula
[tex]A=\dfrac{28.27\times10^{-12}}{1\times10^{-13}}[/tex]
[tex]A=282.7\ m^2[/tex]
We need to calculate the distance
Using formula of area
[tex]A=4\pi r^2[/tex]
Put the value into the formula
[tex]282.7=4\pi\times r^2[/tex]
[tex]r^2=\dfrac{282.7}{4\pi}[/tex]
[tex]r=\sqrt{\dfrac{282.7}{4\pi}}[/tex]
[tex]r=4.74\ m[/tex]
Hence, The distance from harvest mouse to the leaf is 4.74 m.
