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mixas84 [53]
3 years ago
5

A concert loudspeaker suspended high off the ground emits 39 w of sound power. a small microphone with a 1.0 cm2 area is 60 m fr

om the speaker. part a what is the sound intensity at the position of the microphone?
Physics
1 answer:
Gelneren [198K]3 years ago
7 0

As we know that intensity of sound is defined as power received per unit area

so here the power of source is given as

P = 39 W

distance of microphone is given as

d = 60 m

now if loudspeaker is considered as spherical source then we will have

Intensity = \frac{power}{area}

Intensity = \frac{39}{4\pi r^2

here

r = d = 60 m

Intensity = \frac{39}{4\pi (60^2)}

Intensity = 0.86 \times 10^{-3} W/m^2

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ou are sitting in your car at rest at a traffic light with a bicyclist at rest next to you in the adjoining bicycle lane. As soo
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3. Atoms are made up of smaller particles.

According to Dalton's theory, atoms are the smallest particles that make matter, and they are indivisible and indestructible, so they are NOT made up of smaller particles.

4. a solid sphere

In Dalton's theory, atoms are not made of smaller particles, so we can think them as solid spheres.

5. J. J. Thomson

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6. An electron has the same amount of energy in all orbitals.

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7. A hydrogen atom in heavy water has an extra neutron.

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