A Certain Photon, After Being Scattered from a Free Electron $120 ^ { \circ }$

Multiple Choice

A certain photon, after being scattered from a free electron that was at rest, moves at an angle of $120 ^ { \circ }$ with respect to the incident direction. If the wavelength of the incident photon is $0.591 \mathrm {~nm}$ , what is the wavelength of the scattered photon? (melectron $= 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s }$ , $h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s }$ )

A) $0.380 \mathrm {~nm}$
B) $0.550 \mathrm {~nm}$
C) $0 \mathrm {~nm}$
D) $0.591 \mathrm {~nm}$
E) $0.595 \mathrm {~nm}$