ACT SSC Physics — Unit 4

Quantum Energy Levels — Flashcards & Quiz

Quantum energy levels in atoms are discrete allowed states for bound electrons, and ACT SSC Physics Year 12 Unit 4 uses the hydrogen atom as the key example. Transitions between levels absorb or emit photons with energy equal to the level difference, producing the characteristic hydrogen spectrum. The Bohr model explains the spectrum and supports the quantised-energy picture.

Last updated: March 2026