a) Find the momentum of the electron.
The momentum would be as follows:
p = E / c
p= (h(c) / (wavelength)) / c
p = h / wavelength
p = 6.626x10^-34 J s / 0.828x10^-9 m
p = 8.00 x 10^-25 kg m/s
b) Find the kinetic energy of the electron.
Assuming this is a head-on collision, then cosine of the angle would be -1.
wavelength (after) - wavelength (before) = 2(h / m(e) c)
wavelength (after) = 2(h/m(e) c) + wavelength (before)
wavelength (after) = 0.00485 nm + 0.828 nm
wavelength (after) = 0.83385 nm
E = h(c)/wavelength
E(before) = h c / 0.828x10^-9 = 2.4x10^-16 J
E(after) = h c / 0.83385 x10^-9 = 2.38 x10^-16 J
Total change in E = 2.4x10^-16 J - 2.38 x10^-16 J
Total change in E = 3.16x10^-17 J
