Please explain in the easiest way, I’m very dumb lol
In: Physics
I don’t think it does. Binding energy is the amount of energy needed to separate a particle from a system, like releasing an electron bound to an atom. So the larger the binding energy, the more energy you need to put in to get that electron out. If you put exactly the binding energy into that electron then it uses all of that energy to escape the atom and leaves with no extra energy.
If the binding energy is 5eV and you put 8eV into that electron, it uses 5eV to escape the atom and leaves with the left over 3eV.
Sometimes things pull each other towards themselves. Gravity is the most obvious example of this; things with mass pull themselves together.
When stuff makes things move (or accelerate), energy is shuffled around between them (we can define energy very loosely as how much something has been forced to move).
If you lift something up you have to put in energy to do that (you have to do work on the thing). You are forcing it against gravity. So when things fall down they lose energy or give out energy in some form. If you drop stuff it speeds up and smashes into the ground, giving off sound, heat etc..
There is a thing called the “strong interaction” or strong force. It is kind of like gravity in that it pulls stuff (protons and neutrons) together. It is different in that it only works on really, really small scales, and if the things get too close to each other it starts to push them away again.
So if you have a proton and a neutron sitting on their own, and you move them close enough together, the strong force will pull them in, like gravity. If you want to pull them apart, you have to put in energy, or do work on them, to separate them. So you put energy in to pull them apart, you get energy out when they stick together.
The “binding energy” is this energy. It is the energy that you need to stop them being bound to each other; the energy needed to pull them apart.
What is interesting about this binding energy is that it depends on the configuration of stuff. For example, the binding energy of Helium-4 (two protons and two neutrons) is much higher than the binding energy of two deuterium nucleuses (each one proton and one neutron). The binding energy of each bit of deuterium is about 2keV. But the binding energy of Helium-4 is about 28keV. So if you get two deuterium nucleuses, “break them apart” (taking 2keV each for a total of 4keV) and then stick them all together to form Helium-4 (giving out 28keV) you have made 24keV of energy profit. You get out far more energy than you put in. Essentially, the protons and neutrons are “happier” being stuck together as 4 than as pairs; they “fall” towards each other, giving out energy. This is a type of nuclear fusion.
Iron is the atom with the highest binding energy per thing; generally the further you are from iron the lower your binding energy per thing. So anything with more protons and neutrons than iron can be broken up into smaller things, and those will have higher binding energy, so the process will give out energy (nuclear fission). Anything with fewer protons and neutrons than iron can be stuck together to form bigger things, and those bigger things will have higher binding energy, so you will get out energy (nuclear fusion).
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Of course, the really, really interesting thing about binding energy is that we know mass and energy are kind of the same thing (mass is an expression of energy). So if something has less energy it has less mass.
So if you take a single proton, and a single neutron, they each have a certain mass. But if you stick them together to form deuterium they now have 2keV less energy, so they will have an equivalent amount less mass! And if you then stick two of those together to make Helium-4 they have 24keV less energy than the deuterium things did, so even less mass!
When you combine protons and neutrons together you end up with less mass than those protons and neutrons had to start with. This is called a “mass defect.”
Technically this happens with gravity as well (if you lift something up, the mass of the thing and the Earth goes up very slightly) but the numbers are far too small to be measurable.
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