Main Question or Discussion Point
i have some basic doubts...why is that nuclear fission is done only on heavy nucleus..what stops to perform nuclear fission on lighter nucleus..what are the lighter nucleus that are used for fission if any?
cant you not gain energy? you just transfer it or somethingYes, fission of nucleus lighter than Fe, no energy is gained. And fusion above Fe you dont gain energy.
You see that the peak is around Fe-56; most energy / nucleon in average.
The idea of nuclear-power is to use this binding energy to get a net gain of energy =)
i mean the heat released...what has temperature with anything to do?
on what level do you want the answer?
The first level is that you compare the total (mass and kinetic) energy of the nuclies before and after reaction. The total mass will be smaller or larger after the reaction (if you fissile a nucleus heavier than iron). The "lost" mass is then transformed into kinetic energy of the reaction products.
No this is more complex that this, but still very elementary. When you fuse two protons, you gain 2.22 MeV which is the binding energy of the deutron. Look at this picture:cant you not gain energy? you just transfer it or something
and dont you need about 300 million degrees to have fissio/fussion (forgot which one is where you combine two molecules) be a viable source without wasting energy put into it.
Dont know how that is done in theory, only empiracally. Well approx 80% of the energy is carried away by the fissile products, the rest is shared by the neutrons, gamma etci mean the heat released...
so are u saying that only the energy released can be found...what are the different energies released, is it only heat ...is there anyway so that we can find the energy released which is in the form of heat...
ya i have no clue what that link is trying to say. i kinda get that h4 is like the most productive.No this is more complex that this, but still very elementary. When you fuse two protons, you gain 2.22 MeV which is the binding energy of the deutron. Look at this picture:
When you go towards iron from H, you bind the nucleus harder and harder, so when you fuse togheter nucleis up to Iron, energy is gained. You get more energy than you put in. But if you fuse two nucleis heavier than iron, the system is more loosley bound, and you get less energy than you put in.
Standard thing you should know in introductory nuclear physics.
the temperature u mentioned is low i think...cant the fission reactions produce million kelvin temperature..is it so,only fusion can produce million kelvin of temperature...yes the fission products are random, they follow a distribution. Se for example:
So therefore, the expression for how much energy that is relased is (semi)emperically measured.
In a fission reactor using water as moderator. the water is boiling. The rods with the Uran is approx 800K, if i remember correct, was three years scince I had nuclear reactor science on the shedule =)
I dont know if nucleis with so low mass-number is instable due to neutron fission. And it also depends of you want to use thermal neutrons or higher energy neutrons, or maybe even have protons as probes.is it possible atleast theoritically to bombard a lighter nuclues than uranium and having Atomic number >60 if we use a very high energy neutron...so that there wont be any need for uranium in future if this is possible...