Compton Scattering: Solving for E with $\phi = 1/4\pi$

AI Thread Summary
The discussion revolves around solving for energy in Compton scattering with a scattering angle of φ = 1/4π. The initial calculations yielded an energy of E = 1.75 MeV, which was confirmed by another participant using the Compton relationship. However, it was noted that the equation used for the wavelength change was incorrect; the correct equation involves (1 - cos φ) rather than cos φ. Despite the error in the equation, the final energy result remained accurate. The conversation highlights the importance of correct formula application in physics problems.
Pushoam
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Homework Statement


upload_2017-12-28_0-15-42.png


Homework Equations

The Attempt at a Solution

## \lambda' = 2 \lambda ##

## \lambda' - \lambda = \lambda = \frac { h} { mc} \cos{ \phi } ##

Here, ## \phi = \frac { pi} 4 ## is the angle between photon's original line of motion and its line of motion after scattering.

Putting the values, I got E = ## \frac { hc} {\lambda } ## = 1.75 MeV, i.e. option (a).

Is this correct?
[/B]
 

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The Compton scattering equation is incorrect, but the answer is (surprisingly) correct. ?
 
Hi
I have the same result (Ei=1.75 MeV) if I consider the Compton relationship$$E_{s}=\frac{E_{i}}{1+\frac{E_{i}}{mc^{2}} \left( 1-cos\theta \right) } $$Es=Ei/2
Sorry kuruman is the fastest
 
kuruman said:
The Compton scattering equation is incorrect, but the answer is (surprisingly) correct. ?
Because I did the right calculation and wrong typing.
The following is wrong:
Pushoam said:
## \lambda' - \lambda = \lambda = \frac { h} { mc} \cos{ \phi }##
The correct one is :
## \lambda' - \lambda = \lambda = \frac { h} { mc} ( 1 - \cos{ \phi })##
 
PSRB191921 said:
Sorry kuruman is the fastest
How did you get to know this? He has not shown the solution.
 
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