Nuclear fission

Question 1

In a reactor, explain how the graphite core and the movable rods are used to maintain and control the chain reaction

Answer 1

-The graphite core slows down the neutrons released during nuclear fission making them more likely to be absorbed by other fuel rods and sustain the chain reaction

• the control rods, made of materials like boron which absorb nuetrons, can be raised or lowered to adjust the rate of the reaction preventing runaway reactions. When the rods are inserted they absorb more neutrons which slows down the chain reaction and reduces the amount of heat produced.
• when neutrons collide with graphite atoms they lose energy and are slowed down.

Question 2

In a fusion reaction, two hydrogen nuclei are forced together to form a
helium nucleus.
Explain why a very high temperature is needed for this reaction to happen

Answer 2

It provides the hydrogen nuclei with enough kinetic energy to overcome their mutual electrostatic repulsion and fuse together. At high temperatures, the nuclei move rapidly, increasing the likelihood of collisions ollins with sufficient energy to breach the “coulomb barrier and fuse, forming a helium nucleus

Question 3

What is nuclear fission?

Answer 3

Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy

Question 4

What type of energy is released in nuclear fission?

Answer 4

Kinetic energy

Question 5

What causes nuclear fission?

Answer 5

Fission occurs occurs when a neutron collides with the nucleus of a heavy atom and causes it to split into two smaller nuclei and releases kinetic energy. This process can create a chain reaction where the released neutrons cause more fission events.