Consider the figure for photoemission. How would you reconcile this with the law of conservation of momentum? Note that light (photons) has momentum in a different direction than the emitted electrons.
(N/A) When an incident photon is absorbed by the metal surface,its momentum is transferred to the entire metal lattice (the system of atoms).
Since the mass of the metal lattice is extremely large compared to the mass of an electron,the recoil velocity of the lattice is negligible.
The momentum of the incident photon is balanced by the combined momentum of the emitted photoelectron and the recoil momentum of the metal lattice.
Therefore,the total momentum of the system (photon + metal) is conserved in accordance with the law of conservation of momentum.
Since the mass of the metal lattice is extremely large compared to the mass of an electron,the recoil velocity of the lattice is negligible.
The momentum of the incident photon is balanced by the combined momentum of the emitted photoelectron and the recoil momentum of the metal lattice.
Therefore,the total momentum of the system (photon + metal) is conserved in accordance with the law of conservation of momentum.
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