When the products of fission have less mass than the starting material, it means that energy has been released. This is the core principle behind nuclear energy.

Here's a breakdown:

* Nuclear Fission: This is the process where a heavy atom's nucleus (like uranium) is split into two or more lighter nuclei (fission products).

* Mass-Energy Equivalence: Einstein's famous equation, E=mc², explains that mass and energy are interchangeable.

* Binding Energy: The nuclei of atoms are held together by a strong force called the strong nuclear force. This force releases energy (binding energy) when it forms. Larger nuclei have a lower binding energy per nucleon (proton or neutron) compared to smaller nuclei.

* Energy Release: When a heavy nucleus splits, the resulting smaller nuclei are more tightly bound together (higher binding energy per nucleon). This means they have a lower overall mass. The difference in mass, which is a tiny amount, is converted into a massive amount of energy.

In simpler terms: Imagine a heavy object being broken into two smaller pieces. The pieces combined are slightly lighter than the original object, and the missing mass is released as energy.

Consequences of Energy Release:

* Heat: The released energy primarily manifests as heat, which is used in nuclear power plants to generate electricity.

* Radiation: Fission also releases various forms of radiation, which pose safety hazards and need to be carefully managed.

Let me know if you want to explore any specific aspect of this in more detail!