- #1
T.O.E Dream
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Is the air pressure near an object making lots of noise (e.g. engine, speaker) higher than the air around it?
Equal Amplitude for Active Noise Control Headphones?
- Thread starter T.O.E Dream
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In summary, the air pressure near an object making lots of noise is not necessarily higher than the air around it. Sound is air pressure fluctuations, with a sound wave including an up and a down. The fluctuations are more dramatic near the object, resulting in the highest highs and equal lows. The amplitude of the wave directly affects the volume of the sound. Insulation can lower the intensity of these fluctuations and reduce the volume of the sound. In active noise control headphones, the amplitude of the sound must be the same for it to cancel out, meaning the volume must also be the same.
- #2
russ_watters
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In total no. Sound is air pressure fluctuations, but a sound wave includes an up and a down.
- #3
Archosaur
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Going further, though, the fluctuations are more dramatic near the object, meaning it will have the highest highs, but again, equaly low lows.
- #4
T.O.E Dream
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If I understand it right sound means that the air pressure increases then decreases and so on? Is the more dramatic the fluctuations the louder the sound?
- #5
T.O.E Dream
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In other words if I had a device that measures air pressure it should be going up and down and up and down. And the further it goes up and down the louder the sound?
- #6
DaveC426913
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Yes. The amplitude of the wave is directly resultant in the volume of the sound.
You could label this diagram with air pressure notches up the Y-axis:
- 0 air pressure at the origin (lower left corner) of the graph
- low air pressure up the y-axis to the x-axis
- ambient air pressure at the x-axis
- high air pressure up the y-axis off the chart
The diagram represents a sound steadily increasing in volume from left to right.
You could label this diagram with air pressure notches up the Y-axis:
- 0 air pressure at the origin (lower left corner) of the graph
- low air pressure up the y-axis to the x-axis
- ambient air pressure at the x-axis
- high air pressure up the y-axis off the chart
The diagram represents a sound steadily increasing in volume from left to right.
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- #7
T.O.E Dream
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And how does insulation lower the intensity of these fluctuations (i.e. lower the volume of the sound)?
- #8
DaveC426913
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Is this homework?T.O.E Dream said:
How do you think insulation affects the sound?
- #9
T.O.E Dream
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I'm wondering something about active noise control headphones. It says that the amplitude must be the same for the sounds to cancel out, does that mean the volume (or loudness) of the sound must be the same?
- #10
DaveC426913
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Yes.T.O.E Dream said:
FAQ: Equal Amplitude for Active Noise Control Headphones?
What is air pressure and how does it affect sound?
Air pressure is the force exerted by the weight of air molecules in a specific area. It affects sound by determining how far sound waves can travel. In areas with high air pressure, sound waves can travel further and be heard more clearly, while in areas with low air pressure, sound waves cannot travel as far and may be less audible.
How is air pressure measured?
Air pressure is typically measured using a barometer, which measures the weight of the air pressing down on a certain area. The unit of measurement for air pressure is usually in pascals (Pa) or millibars (mb).
What factors can change air pressure?
Air pressure can be affected by temperature, altitude, and weather conditions. As temperature increases, air expands and becomes less dense, resulting in lower air pressure. As altitude increases, there is less air above, causing lower air pressure. Changes in weather, such as the movement of high and low pressure systems, can also affect air pressure.
How does air pressure impact our daily lives?
Air pressure has a significant impact on our daily lives, as it affects weather patterns, flight and transportation, and even our own bodies. Changes in air pressure can cause headaches and discomfort, while extreme changes can lead to more serious health issues.
How do we use air pressure to create sound?
Sound is created when an object vibrates and causes air molecules to move. These vibrations create sound waves that can travel through air. In musical instruments, air pressure is used to vibrate a specific material, such as a string or reed, to create sound. In vocalization, air pressure is used to vibrate the vocal cords and produce speech or singing.