Intensity of red laser vs blue laser

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The discussion centers on comparing the intensity of blue and red lasers, highlighting that intensity is influenced by amplitude rather than wavelength. Red lasers have a longer wavelength and lower frequency compared to blue lasers, but this does not directly determine intensity. The conclusion is that without specific information about the amplitude of each laser, one cannot definitively determine which has higher intensity. Participants agree that amplitude is the key factor in assessing intensity. Overall, the conversation emphasizes the importance of amplitude in understanding laser intensity.
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1. Homework Statement :
Consider two lasers, one blue and one red. Which of the two lasers has the higher intensity?


2. these are my choices:
The blue one.
Cannot be decided based on the information given.
The red one.


3. The Attempt at a Solution :
The difference between these two lasers is their wavelength. Red has a higher wavelength than blue. Both have the same velocity, so red also has a lower frequency than blue (because v = wavelength * frequency). However, intensity depends on amplitude. (this is where I'm not sure) Amplitude does not depend on wavelength even though the displacement depends on both amplitude and wavelength, so we cannot decide with the given information.

am i right or totally off?
 
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You are completely right.
 
I also think the intensity is given by the amplitude.. Just like volume in sound is given by it.
 

Thread 'Help needed with Elliptic Integrals'

I want to find the solution to the integral ##\theta = \int_0^{\theta}\frac{du}{\sqrt{(c-u^2 +2u^3)}}## I can see that ##\frac{d^2u}{d\theta^2} = A +Bu+Cu^2## is a Weierstrass elliptic function, which can be generated from ##\Large(\normalsize\frac{du}{d\theta}\Large)\normalsize^2 = c-u^2 +2u^3## (A = 0, B=-1, C=3) So does this make my integral an elliptic integral? I haven't been able to find a table of integrals anywhere which contains an integral of this form so I'm a bit stuck. TerryW
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