Two people are talking at a distance of 3.0 m from where you are, and
you measure the sound intensity as 1.1'10 W/m. Another student
is 4.0 m away from the talkers. Calculate a reasonable estimate for the
sound intensity that the other student measures.
A) 62' 10-8 W/m2
B) 1.5'10-7 W/m2
8.3' 10-8 W/m2
D) 7.8'10-7 W/m2

Respuesta :

Answer:

The sound intensity that the other student measure, I₂ is expected to be;

A) 6.2 × 10⁻⁸ W/m²

Explanation:

The measure of sound intensity is given by the following formula;

[tex]I = \dfrac{P}{4 \cdot \pi \cdot R^2}[/tex]

[tex]\dfrac{I_2}{I_1} = \dfrac{R_1^2}{R_2^2}[/tex]

Where;

I = The intensity

R = The radius

P = The power of the sound

Whereby we have;

The distance of the two people talking, R₁ = 3.0 m

The measure of the sound intensity, I₁ = 1.1 × 10⁻⁷ W/m² (from an online source)

The distance of the other student from the two people talking, R₂ = 4.0 m

Therefore, the estimate of the sound intensity, I₂, is given as follows;

[tex]{I_2} = \dfrac{R_1^2}{R_2^2} \times {I_1}[/tex]

[tex]{I_2} = \dfrac{(3.0 \, m)^2}{(4.0 \, m)^2} \times 1.1 \times 10^{-7} \ W/m^2 = 6.1875 \times 10^{-8} \ W/m^2[/tex]

I₂ = 6.1875 × 10⁻⁸ W/m²

∴ The sound intensity that the other student measure, I₂ ≈ 6.2 × 10⁻⁸ W/m²