Question 1

Which process is primarily responsible for generating energy in a standard commercial nuclear power plant?

Accepted Answer

Nuclear Fission. Nuclear fission involves splitting a heavy nucleus into smaller parts to release energy. This process is controlled using fuel rods and moderators within the reactor core. It currently provides a significant portion of the world's carbon-free electricity.

Question 2

Which isotope is most commonly used as fuel in the majority of nuclear reactors worldwide?

Accepted Answer

Uranium-235. Uranium-235 is the primary fissile isotope used because it can sustain a nuclear chain reaction. Although it makes up only about 0.7% of natural uranium, it is enriched for reactor use. Uranium-238 is much more abundant but is non-fissile by itself.

Question 3

What is the function of a 'Moderator' in a nuclear reactor?

Accepted Answer

To slow down neutrons. A moderator slows down fast-moving neutrons so they can effectively cause further fission in U-235. Common moderators used in reactors include ordinary water, heavy water, and graphite. This slowing down process is essential for maintaining a steady chain reaction.

Question 4

Which material is frequently used for control rods to regulate the rate of fission in a reactor?

Accepted Answer

Boron. Control rods are made of neutron-absorbing materials like boron or cadmium. By inserting or withdrawing these rods, the number of available neutrons can be precisely managed. This mechanism allows operators to increase, decrease, or stop the power output.

Question 5

Where was the world's first commercial nuclear power plant, Obninsk, located?

Accepted Answer

Soviet Union. The Obninsk nuclear power plant began operations in 1954 in the Soviet Union. It was the first plant to successfully connect nuclear-generated electricity to a power grid. This event proved the feasibility of using atomic energy for peaceful domestic purposes.

Nuclear Power — Set 1