Aviation Institute of Maintenance (AIM) Block 1 Practice Test

Latent heat is the energy involved in changing a substance from one state to another, such as solid to liquid or liquid to gas. This energy is absorbed or released at a constant temperature during the phase change, so the temperature doesn’t rise or fall while the change occurs. For melting, the absorbed energy is the latent heat of fusion; for boiling, it's the latent heat of vaporization. When the substance freezes or condenses, that same latent heat is released. This is different from sensible heat, which is the energy that raises or lowers temperature without changing the substance’s phase.