Where does all the energy in nuclear reactions come from?

Question

the law of conservation of energy states that energy cannot be created or destroyed, so where does all the energy come from?

Answer 1

Be careful with conservation laws. Its mass-energy that is conserved, and even this is frame dependent.

The energy released in nuclear reactions arises from the different binding energies of the nucleons between the starting nucleus and the resulting ones. For nuclei larger than iron, the binding energy is higher the smaller the nucleus (ie particles are more tightly bound). It is the balance between the electrostatic and strong nuclear forces that give rise to this.

But because energy and mass are equivalent, the difference in binding energy is mostly seen as a difference in mass. In fact, around 80% of the mass of the nucleus arises from the binding energy of the quarks in the nucleons.

Answer 2

The law of conservation of mass and the law of conservation of energy were two separate laws until Einstein came along and showed the equivalence of mass and energy with his famous equation

E = m.c^2

and in nuclear reactions, it is the m which is converted into E. since c is a very large number, lot of energy is released from small amounts of m.

Similarly under the right conditions, mass is produced from energy.

Answer 3

The protons and neutron in a nucleus are tightly bound by the hadronic force, but the binding varies greatly for different nuclei. This means different nuclei contain different amounts of potential energy, which is reflected (as with all internal energy) in their mass. By transmuting from loosely bound to tightly bound nuclei, the potential energy it turned into kinetic energy, aka heat and radiation. Qualitatively, it's similar to chemical reactions, but at a greater scale since the nuclear binding energies are greater than those of chemical bonds.

Answer 4

Atoms contain extremeley huge amount of energy.
Because matter = energy (E=mc2 where E energy and m is mass and c is speed of light)

Therefore if you break an atom, or if matter frees its energy in an other word, it's big...

Answer 5

From potential energy in the nucleus, which is changed into energy.

Answer 6

E=MC^2

Answer 7

from d neuclus[potential]