WAEC Physics 2023 Paper

Concept:When an electron jumps from a higher energy level to a lower one, it releases energy as a photon.Explanation:The electron moves from $n=4$ to $n=2$.In the Bohr model, $n=4$ is a higher energy level than $n=2$.So the electron loses energy during this transition.This lost energy is emitted as a single photon.The photon energy equals the difference between the two levels:$E_{\text{photon}} = E_4 - E_2$.A photon is absorbed only when an electron jumps from a lower to a higher level, which is not the case here.Thus, exactly one photon is emitted in this direct transition.Answer:B. A photon is emitted.