Question

2025 astronomy fall final exam (1st semester)
what is emitted from an atom when an electron falls from a higher energy level to a lower energy level?
○ photon
○ neutron
○ electron
○ proton

Explanation:

In atomic physics, when an electron transitions from a higher energy level to a lower energy level, the energy difference is released as a photon. Neutrons, protons are in the nucleus and not involved in electron energy level transitions in this way, and an electron falling to a lower level doesn't emit another electron.

Answer:

A. Photon