An x-ray beam (85.97 MeV) strikes a proton at rest and scatters the x-rays through an angle of 100°. What is the wavelength, in pico-meters, of the scattered x-rays?

Respuesta :

ANSWER

[tex]466,000\text{ pm}[/tex]

EXPLANATION

Parameters given:

Energy of X-ray beam = 85.97 MeV

Scattering angle, θ = 100°

To find the wavelength of the x-ray beam, we have to apply the Compton Effect formula:

[tex]\lambda^{\prime}-\lambda=\frac{h}{m_0c}[1-\cos\theta][/tex]

where λ' = wavelength of the scattered x-ray

λ = wavelength of the incident x-ray

h = Planck's constant

moc = 1.67 * 10^(-27)

First, we have to find the wavelength of the incident x-ray. To do this, apply the formula for energy:

[tex]\begin{gathered} E=\frac{hc}{\lambda} \\ \\ \lambda=\frac{hc}{E} \end{gathered}[/tex]

Therefore, the wavelength of the incident x-ray is:

[tex]\begin{gathered} \lambda=\frac{6.626*10^{-34}*3*10^8}{85.97*10^6*1.6*10^{-19}} \\ \\ \lambda=1.45*10^{-14}\text{ m} \end{gathered}[/tex]

Now, substitute the given and obtained values into the equation for Compton's effect and solve for λ':

[tex]\begin{gathered} λ^{\prime}-1.45*10^{-14}=\frac{6.626*10^{-34}}{1.67*10^{-27}}*(1-\cos100) \\ \\ λ^{\prime}-1.45*10^{-14}=\frac{6.626*10^{-34}}{1.67*10^{-27}}*1.174 \\ \\ λ^{\prime}-1.45*10^{-14}=4.66*10^{-7} \\ \\ λ^{\prime}=4.66*10^{-7}+1.45*10^{-14} \\ \\ λ^{\prime}=4.66*10^{-7}\text{ m}=466,000\text{ pm} \end{gathered}[/tex]

That is the wavelength of the scattered x-rays.

RELAXING NOICE
Relax