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3 years ago

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The sound intensity at the ear of passenger in a car with a damaged muffler is 8.0 × 10-3 W/m2. What is the intensity level of t

his sound in decibels? Use the threshold of hearing (1.0 × 10-12 W/m2) as the refere

1 answer:

Mama L [17]3 years ago

4 0

Answer:

99 dB

Explanation:

We have given that sound intensity with a damaged muffler =8× $10^{-3}$

we have to find the intensity level of the this sound in decibels

for calculating in decibels we have to use the formula

β= $10log\frac{I}{I_0}$

= $10log\frac{.008}{10^{-12}}$

=10 log8+10 log $10^{9}$

=10 log8+90 log10

=10×0.9030+90

=99 dB

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Answer:

1838216 J

Explanation:

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40 km/h = 11.11 m/s

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$\text{Efficiency of the heat engine} = \eta = 26\% = 0.26$

$\text{Energy taken in by the heat engine during each cycle} = Q_h$

$\text{Energy exhausted by the heat engine in each cycle} = Q_c = 8.55*10^3 J$

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Therefore the interval for each cycle is 0.75s

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3 years ago