What is the relationship between Intensity and Frequency. From what I've found on the forums I've concluded that they are independent of one another, but EK physics says "Know that intensity increases with the square of the amplitude and the square of the frequency for all waves." Whats right?
Intensity and Frequency EK vs Nova Physics
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Thread moved. This type of question belongs in the Study Q&A forum.
Intensity is not simply the amplitude of a wave, and intensity and frequency are related as EK says, but that doesn't mean that a higher frequency wave necessarily has higher intensity. Intensity is a function of many things, including amplitude, velocity, and density. For the MCAT, most questions that you will be asked will not require this. What they will test you is if you understand the idea that a bright light can have low frequency, or that a loud sound can be of very low pitch.
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*actually looks up*....
wow...I never intensity was related to so many variables.
OP, if you're interested, supposidely, intensity is proportional to the "square of the modulus of the electric field vector."
This sites explains it very nicely. With very simple math too!!
http://www.dcmsistemes.com/medidasi.html
wow...I never intensity was related to so many variables.
OP, if you're interested, supposidely, intensity is proportional to the "square of the modulus of the electric field vector."
This sites explains it very nicely. With very simple math too!!
http://www.dcmsistemes.com/medidasi.html
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For an EM Wave, Intensity is proportional to the Square of the Energy (where E = hf). So if your frequency doubles, the Energy doubles but your Intensity increases by a factor of 4.
The amplitude of any wave only tells you how much energy the wave has. It is not related to Velocity, Frequency, or Wavelength. (This is according to TPR).
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Check this site out: http://physics.info/intensity/
I ∝ ρ (Density)
I ∝ f² (frequency)
I ∝ v (velocity)
I ∝ Δx² max (Amplitude / Displacement)
I ∝ ρ (Density)
I ∝ f² (frequency)
I ∝ v (velocity)
I ∝ Δx² max (Amplitude / Displacement)
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No, intensity does depend on frequency. Hence why it is proportional to the square of the frequency. If Intensity was independent of frequency, then a change in frequency would not affect Intensity. Based on what was said above, you can see that this isn't true. There are various equations for intensity, each expressed using different variables. The main thing you should take away is everything I wrote in my last post. I think the most important one to remember is how frequency or energy effects intensity, and realizing that intensity is directly proportional to the square of energy/frequency.
Intensity is dependent on frequency, but a high frequency wave is not necessarily more intense than a low frequency wave. On the other hand, a higher frequency wave necessarily has more energy per particle than a lower frequency wave (frequency and energy are only dependent on each other).
I = 2π^2(`😉f^2(v)A^2max
Where A = dXmax (amplitude), rho is density of medium and frequency is, well, f!
I don't think this is a "memorize" MCAT equation but shows that intensity of a wave depends on square of freq and square of amplitude. A post above also said this, but didn't include the equation from which it is derived.
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