Question

An x-ray photon whose initial frequency was 1.5 10^19 Hz

emerges from a collision with an electron with a frequency of

1.2 10^19 Hz. How much kinetic energy was imparted to the

electron?​

Answer 1

Explanation:

It is an elastic collision, where the kinetic energy before and after collision would remain constant.

So, Kinetic energy of initial X-ray = (Kinetic energy of final X-ray) + (Kinetic energy of emitted electron).

or, Kinetic energy of the emitted electron = (Kinetic energy of initial X-ray) - (Kinetic energy of final X-ray)

or, K.E (electron) = (1.5–1.2) x 10^19 x 6.623 x 10^-34 Joule; [from, E= hʋ, h is the Plank constant]

or, K.E (electron) = 0.3 x 6.626 x 10^-15 J = 1.9878 x 10^-15 J

or, K.E (electron) = (1.9878 x 10^-15)/(1.6 x 10^-19) eV = 1.2423 X 10^4 eV