Nuclear Physics Flashcards
Define mass defect
The difference between the mass of the separated nucleons and the mass of the nucleus.
Define binding energy
The minimum energy required to separate a nucleus into its constituent protons and neutrons.
Explain the role of fuel rods.
They contain the uranium / fissile material needed in fission reactions.
Explain the role of the control rods.
Rods (boron or cadmium) that control the rate of nuclear fission by absorbing neutrons.
Explain the role of the moderator.
- Slows down fast moving neutrons and turn them into thermal neutrons.
- Slower moving neutrons have a greater chance of causing fission.
(water, graphite, carbon)
Why must fusion take place at high temperatures?
High temp -> particles moving fast -> particles come closer enough so that strong nuclear force can bring about fusion.
Explain how fission reactions produce energy.
There is a difference in energy between the binding energy of uranium and the binding energy of the sum of the products. This energy is released.
Why does a neutron not have binding energy?
It cannot be split any further.
Describe the process of induced nuclear fission.
Large uranium nucleus absorbs a neutron.
Large nucleus is split into smaller, daughter nuclei.
Explain why protons must have a large velocity for fusion to take place and for the protons to remain together.
Repulsive force slows the protons down.
High velocity needed so that protons get close enough for ATTRACTIVE strong nuclear force to take effect.
