1. LECTURE 9.2 – E = mc2

2. Today’s Learning Targets
LT 9.2 – I can explain why energy is released in a nuclear fusion/fission reaction and I can calculate the amount of energy released.

3. What are nuclear fusion and fission?

4. I. Nuclear Fusion Fusion – When two things combine into one
Nuclear fusion is when two atomic nuclei fuse into one new atom

6. II. Nuclear Fission Fission – Splitting of an item into two
Nuclear fission is when a very heavy nucleus splits into a smaller, more stable nucleus

8. What is Einstein’s Equation?

9. I. Conservation of Matter
Matter cannot be created or destroyed, it only can change forms.
Sometimes, when compounds react the mass of the atom is not the same as the mass of protons and neutrons alone.
The lost mass is converted into energy!

10. II. The Equation E = energy (measured in Joules)
m = mass (measured in kilograms)
c = the speed of light, 3.0 x 108 m/s or 300,000,000

11. Class Example
You have a 2 kg object. Calculate the amount of energy that would be produced if you were to convert all of this mass into energy. (c = 3.0 x 108 m/s)

12. Table Talk
You have a 5 kg substance. How much energy would be produced if this mass was converted to energy? (c = 3.0 x 108)

13. Stop and Jot
If you produced 500,000 J of energy when you converted the mass of a substance to energy, then what was the original mass of the substance? (c = 3.0 x 108)

14. Applications of E=mc2
If we know the energy associated with the loss of mater in the nucleus, then we can use this energy for both good and bad.
Common examples:
Nuclear energy
Atomic Bomb
Smoke detectors
Radio-isotopes in medicine