Among the following chemical elements, which is the one used as a moderator in a nuclear reactor?

Options :
  1. Helium
  2. Radium
  3. Thorium
  4. Graphite
Answer and Explanation :-

Answer: Option 4


A gas-cooled reactor (GCR) is a nuclear reactor that uses graphite as a neutron moderator and carbon dioxide (helium can also be used) as coolant. Although there are many other types of reactor cooled by gas, the terms GCR and to a lesser extent gas cooled reactor are particularly used to refer to this type of reactor. In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235. Commonly used moderators include regular (light) water (roughly 75% of the world's reactors), solid graphite (20% of reactors) and heavy water (5% of reactors). Beryllium has also been used in some experimental types, and hydrocarbons have been suggested as another possibility.

How do you rate this queston?  Very Easy  Easy  Average  Above Average  Tough

Previous Question : The estimation of age of most ancient geological formations is done using which of the following met...

Next Question : Which of the following different types of radiations have the most penetrating power?

Click here for online test on General Science


 (Getemail alerts when others member replies)

When you find yourself in need of spiritual nourishment, it is in the opportunities to serve others that you will find the abundance you seek.
-Steve Maraboli Life the Truth and Being Free