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Cloud [144]
3 years ago
8

A surface receiving sound is moved from its original position to a position three times farther away from the source of the soun

d. The intensity of the received sound thus becomes
a. three times as high,
b. nine times as high.
c. nine times as low.
d.three times as low.
Physics
1 answer:
vazorg [7]3 years ago
6 0

Answer:

c. nine times as low.

Explanation:

Sound intensity is defined as the acoustic power transferred by a sound wave per unit of normal area to the direction of propagation:

I\propto \frac{1}{A}

Since the sound wave has a spherical wavefront of radius r, then the area is given by:

A=4\pi r^2

Here r is the distance from the source of the sound. Thus sound intensity decreases as:

I\propto \frac{1}{4\pi r^2}\\\\I'\propto \frac{1}{4\pi r'^2}\\\\I'\propto \frac{1}{4\pi (3r)^2}\\\\I'\propto \frac{1}{9} \frac{1}{4\pi r^2}\\\\I'\propto \frac{1}{9} I

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A 0.11 N m torque is applied to a fan that was initially at rest. The fan has moment of inertia of 0.034 kg m2. Determine the ki
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Answer:

Explanation:

From the given information:

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Given that;

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Hence, we can conclude that star X is more luminous by a factor of 16

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