00:01
For this exercise, we have a photon incident on an electron, and then the photon scatters off at an angle of 29 .5 degrees.
00:13
And we are given the information that the final wavelength, the wavelength of the scattered photon, is 2 .81 picometers, which is the same as 2 .81 times 10 to the minus 12th.
00:33
Meters.
00:36
Okay.
00:37
And we're asked to find in question a, what is the wavelength of the incident photon? so we're going to calculate lambda i.
00:51
Let's remind that according to compton's formula, we have that the wavelength of the scattered photon is the wavelength of the incident photon plus h over the mass of the electron c, 1 minus cosine of theta, the angle, the scattering angle.
01:14
And we have the lambda s, it's 2 .81 times 10 to the minus 12 meters equals lambda i, plus h over mec is 2 .43 times 10 to the minus 12.
01:36
That's a constant times 1 minus the cosine of 29, which is 029 .29, consign of 29, which is 0 .87.
01:51
So this is going to be 2 .81 times 10 to the minus 12 equals lambda i.
02:03
Plus 0 .32 times 10 to the minus 12...