Questions tagged [attenuation]
The attenuation tag has no usage guidance.
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Determining the photon beam intensity to confirm the placment of an object in a iradiated chamber [closed]
A parallel bundle of monoenergetic photons is used for imaging in the configuration below. The bundle passes through a layer of water with a thickness of 1 cm, then through a zone where a cube with a ...
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Getting the spectrum of light source at high intensity (for low transmittance measurement)
I am trying to measure the transmittance spectrum through a liquid sample using a visible-NIR spectroscopy (a spectrometer connected to a fiber optics and a collimating lens at the end), with tungsten-...
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Calculation of Ultrasonic Attenuation Coefficient
Hello I have a conceptual question regarding calculating the ultrasonic attenuation coefficient for a transmitted wave within a solid material. I have seen Beer's Law used to calculate the attenuation ...
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Beer's Law ultrasound attenuation, account for spherical spreading?
I've seen Beer's Law for narrow beam written as:
$$
I = I_0 \cdot e^{-\alpha x}
$$
${\alpha }$ - attenuation coefficient (depends on absorption and scattering),
$I_0$ - initial intensity,
$I$ - ...
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How can we describe the attenuation of sound in an expanding gas cloud in a vacuum?
For example, suppose a spaceship explodes. The sound of the explosion will travel in the expanding cloud of escaping gas. I gather that it should rapidly weaken and the pitch should drop, but I'd like ...
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Does EM wave lose energy in air?
Light is EM wave.
As it travels through vacuum, it does not lose energy but I am wondering if it travels in air, just imagine light in your home. Before it reaches your eye, it has to travel through ...
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What is the formula for the power of a laser at distance $x$ (taking attenutation into account)?
While this is inspired by science fiction, if I have a hypothetical laser weapon that needs to meet a very high energy requirement of energies of the order $ 1 \times 10^{22} $ Joules, what formula ...
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Why does audio signal amplitude always fall off at higher frequencies?
In the frequency spectrum of every real audio sample that I've ever seen, the amplitude of the frequency components is always higher at low frequencies, then rapidly falls off at higher frequencies.
...
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How do you calculate light attenuation by wavelength at a given air mass coefficient?
I am trying to get a good view of light wavelength distribution as a function of viewing angle, with a specific interest as $z \approx 90^\circ$ near the horizon (sunrise/sunset). Air mass ...
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The impact of electron density on photoelectric effect
I'm a second year radtion therapy student and i'm looking at the attentuation of KV energy beams. I'm wondering why for the photoelectric effect to occur does there need to be a high amount of 'inner'/...
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How does wavelength affect scattering?
Let's say that I have a detector and a few sources of light (think lightbulbs). The sources are all the same power and emit different colours of light. We're on the surface of Earth.
As I walk further ...
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Effective optical depth using Beer-Lambert law for non-linear attenuation?
Currently I have a gas with a density that follows and inverse square law in distance, $r$. Given that I know the mass attenuation coefficient of this gas, I wish to calculate an effective optical ...
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What is the maximum distance that music is transmitted through the air?
I would like to hear your advice on which method to use to transmit music or speech in a frequency band that is sensitive to the human ear up to 3km. Everyone knows that the higher the frequency, the ...
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Collisional cross-section from attenuation factor
I am trying to find the mean free path of silver atoms travelling through air (I am given the temperature, pressure and that they are attenuated by a factor $2.72$ in a distance of $10^{-2}$m).
I know ...
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Does the inverse square law of sound change with frequency?
High frequency For example, I try to chase wild animals by creating a high sound pressure level with a frequency of 17 kHz or higher, but I can't calculate the initial sound pressure.
One thing is ...
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