In an experiment on photoelectric effect, a photon is incident on an electron from one direction and the photoelectron is emitted almost in the opposite direction. Does this violate conservation of momentum?
The photoelectron is emitted in the opposite direction to that of the direction of incident photon, does not violate the conservation of momentum. The conservation of momentum is based on the Newton’s third law which says that the forces acting during collision are equal and opposite. Thus, during collision of photon and electron, the photoelectron is emitted in the opposite direction.