Physics
Physics, 04.03.2021 01:40, golderhadashaowtatz

PLEASE PLEASE HELP ME OUT, 45 POINTS+BRAINLIEST Imagine that a firecracker explodes sending a sudden burst of sound waves traveling out in all directions from the single point where the firework exploded. The series of spheres below illustrates the leading edge of that sound wave as it travels outward over time.

Let’s suppose that the total energy transferred to the sound wave is 10.0 Joules, which is spread evenly in all directions. After 1 second, the sound energy is still concentrated in a relatively small area – the surface area of the sphere shown at far left. Because the energy is concentrated in such a small space, it will still sound very loud to anyone who is close enough to hear it after just 1 second. As time goes on, the sound spreads out over a larger and larger sphere.
In this activity, you will be asked to calculate the surface area of each sphere shown above using the information in the table below. (Recall that the equation for the surface area of a sphere is A = 4 π r 2). You will then calculate how intensity of sound over time by taking the total energy (10.0 Joules) and dividing it by the surface area to determine the energy per square kilometer.

Time
(Seconds)
Total Energy
(Joules)
Radius
(Kilometers)
Surface Area
(km2)
Intensity
(Joules / km2)
1.00
10.0
0.34
1.45
6.90
2.00
10.0
0.68

3.00
10.0
1.02

4.00
10.0
1.36

5.00
10.0
1.70

First calculate the surface area for each of the spheres above, recording your data in the table. The first calculation has been performed for you. (3 points)

Then calculate the intensity of the sound by taking the total energy and dividing by the surface area for each sphere. (3 points)
Finally, answer the three questions below.

Reflection Questions
What general pattern do you notice in the intensity of sound for a listener who is farther and farther away from the initial firework blast? Does this make sense? Why/why not? (5 points)

In your own words, explain why the intensity of sound falls off with the square of the distance from the source of sound. (5 points)

Explain why everyone in a classroom can hear one person speaking, but why a microphone and speaker must be used in a large concert auditorium. (5 points)

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PLEASE PLEASE HELP ME OUT, 45 POINTS+BRAINLIEST Imagine that a firecracker explodes sending a sudde...

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