Question
In the compton effect momentum conservation applies, so thetotal momentum of the photon and the electron is the same beforeand after the scattering occurs. Suppose in figure 29.10 that thedirection of the incident photon is in the + x direction and thatthe scattered photon emerges at an angle of = 90.0, which isin the -y direction. (a) Before the scattering, the total momentumhas an x component. Does it have a y component? (b) After thescattering, the total momentum has an x component. Does it have a ycomponent? (c) Does the momentum of the scattered electron have anx component? (d) Considering your answer to question (b), andconsidering the fact that the scattered photon is moving along the-y axis, does the momentum of the scattered electron have a ycomponent? In each case justify your answer. In figure 29.10 the incident photon has a wavelength of 9.00 x10-12 m. The scattered photon emerges at =90degrees. Find the x and y comonents of the momentum of thescattered electron. In the compton effect momentum conservation applies, so thetotal momentum of the photon and the electron is the same beforeand after the scattering occurs. Suppose in figure 29.10 that thedirection of the incident photon is in the + x direction and thatthe scattered photon emerges at an angle of = 90.0, which isin the -y direction. (a) Before the scattering, the total momentumhas an x component. Does it have a y component? (b) After thescattering, the total momentum has an x component. Does it have a ycomponent? (c) Does the momentum of the scattered electron have anx component? (d) Considering your answer to question (b), andconsidering the fact that the scattered photon is moving along the-y axis, does the momentum of the scattered electron have a ycomponent? In each case justify your answer. In figure 29.10 the incident photon has a wavelength of 9.00 x10-12 m. The scattered photon emerges at =90degrees. Find the x and y comonents of the momentum of thescattered electron.
Explanation / Answer
Hi, We know the mass of electron and that of photon is notsame. a) Before scattering, we have only a photon moving in +vex-direction and electron at rest. So, there is noy-component for momentum before scattering. b) Since momentum must be conserved, thenet y-component of the momemtum afterscattering should be zero. Thus there wont be anyy-component for total momentum after collission. c) Since the scattered photon is moving along -ve y-direction,and since the electron photon masses are different, the anglebetween the scattered photon and recoiled electron will not be90o , i.e., the recoil electron will move making anacute angle with +ve x-axis. Thus it will haveboth x-component and y-component. d) We know the y-component of total momentum after scatteringshould be zero. And the scattered photon already moves in -vey-direction. Hence the electron should have a y-componentof momentum to nullify this. Hope this helps you.