7/21/2019 Refraction of Sound Waves

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Refraction of Sound Waves

Experiment 1

Result

The amplitude of the sound wave increases when a balloon filled with Carbon dioxideis placed between the speaker and the microphone.

Explanation

1. Carbon dioxide is denser than air.

2. The sound wave is refracted approaching the normal when the wave

propagates from the air into the balloon, and away from normal when moving out

from the balloon.

3. s a result, the balloon acts as a biconvex lens and converge the sound wave at

a point.

7/21/2019 Refraction of Sound Waves

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Experiment 2

Result

The amplitude of the sound wave decreases when a balloon filled with Carbon dioxide

is placed between the speaker and the microphone.

Explanation

1. !elium gas is less dense than air.

2. The sound wave is refracted away from the normal when the wave propagates

from the air into the balloon, and closer to the normal when moving out from the

balloon.

3. s a result, the wave is diverged to a wider area and causes the amplitude of

the sound wave decreases.