Monochromatic X-ray photons of wavelength strike free electrons that are initially at rest

PHYSICS · Single correct · A Level · Physics · Particles and radiation · Particles and radiation

Problem

Monochromatic X-ray photons of wavelength

0.014\,\text{nm}

strike free electrons that are initially at rest. Photon 1 is scattered through

30^{\circ}

and photon 2 through

120^{\circ}

(angles measured with respect to the original photon direction). The scattered photon wavelengths are measured to be

0.015\,\text{nm}

and

0.018\,\text{nm}

, respectively. What is the ratio of the kinetic energy of the electron from the

120^{\circ}

event to that from the

30^{\circ}

event? (a)

4.0

(b)

0.30

(c)

3.3

(d)

10