Question

In an experiment on Compton scattering, wavelength of incident $X-ray$ is $1.872$ A.U. Then, the wavelength of the $X-ray$ scattered at an angle of ${90}^0$ is

• A. $1.872$ A.U
• B. $1.896$ A.U
• C. $1.848$ A.U
• D. $0.024$ A.U

Answer 1

Answer: (A)

$1.872$ A.U

According to the Compton's Equation

$\lambda -{\lambda }^{\prime }=\frac{h}{m_{e}c}(1-{\cos }^{}\theta )$

where $\lambda$= inital wavelenth,

${\lambda }^{\prime }$ = final wavelength,

h=Planck's Constatnt,

$M_e$=Mass of electron,

$\theta$=angle of scattering,

Since $\theta$=90, Cos$\theta$=1,

hence RHS =0

hence ${\lambda }^{\prime }=\lambda =1.872A.U$