
Concept explainers
(a)
The sound intensity level right in front of the trumpet.
(a)

Answer to Problem 74P
The sound intensity level right in front of the trumpet is
Explanation of Solution
The energy rate of the trumpet is
Write the formula for the sound intensity level in decibels.
Here,
Write the formula for intensity.
Here,
Write the formula for area.
Here,
Substitute equation (III) in (II).
Conclusion:
Substitute
The sound intensity level right in front of the trumpet is
(b)
The sound intensity level at a distance of
(b)

Answer to Problem 74P
The sound intensity level at a distance of
Explanation of Solution
The energy rate of the trumpet is
Write the formula for the sound intensity level in decibels.
Here,
Write the formula for intensity.
Here,
When the trumpet is giving out waves uniformly in all directions, the sound wave is spread out in uniform spherical shells.
Write the formula for area.
Here,
Substitute equation (IV) in (II).
Conclusion:
Substitute
The sound intensity level at a distance of
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Chapter 12 Solutions
Physics
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