**Lesson resources: **
**Lesson summary:**This lesson corresponds with these next four pages. Energy is matter, and matter is energy. When two nucleons combine, they have less mass than when separate. This difference in mass is due to the energy required to overcome the strong nuclear force holding them together. The equivalence between mass and energy is also apparent in the stability of different isotopes.

**Present key content:**
Students explain Einstein's impact on scientific thought

* (in slide presentation)*.

Students describe the significance of mass-energy equivalence

* (in slide presentation)*.

Students explain Einstein's impact on society

* (in slide presentation)*.