Tag: nuclear physics

Quizzes (6) Questions (198)

Questions Related to nuclear physics

Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

Which of the following is a neutron absorber?

  1. $Pb$
  2. $Ag$
  3. $Cd$
  4. $Cu$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The purpose of neutron absorber is to have a controlled reaction.
The most important neutron absorber is 10B as 10B4C in control rods, or boric acid as a coolant water additive in PWRs. Other important neutron absorbers that are used in nuclear reactors are xenon, cadmium, hafnium, gadolinium, cobalt etc.
Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

Control rods used in nuclear reactors are made of

  1. stainless steel

  2. graphite

  3. cadmium

  4. plutonium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Control rods are used in the nuclear reactor to control the fission rate of uranium and plutonium. These are composed of chemical elements such as cadmium, silver and indium that are capable of absorbing many neutrons without  fissioning themselves.

Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

For making atom bomb, what else is needed except $U^{235}$?

  1. neutron

  2. proton

  3. electron

  4. meson
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The fission of $U-235$ in reactors is triggered by the absorption of a low energy neutron, often termed a "slow neutron" or a "thermal neutron". Other fissionable isotopes which can be induced to fission by slow neutrons are plutonium$-239,$ uranium$-233$, and thorium$-232$.
Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

In a nuclear reactor, moderators slow down the neutrons which come out in a fission process.The moderators used have light nuclei. Heavy nuclei will not solve the purpose, because

  1. The net weight of the reactor would be unbearably high.

  2. Heavy nuclei will break generating unwanted smaller nuclei.

  3. Elastic collision of neutrons with heavy nuclei will not slow them down.

  4. Substances with heavy nuclei do not occur in liquid or gaseous state at room temperature.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In an elastic collision, kinetic energy is transferred most efficiently when the masses of the colliding particles are similar. If a neutron hits a heavy nucleus, it bounces off with almost all its original energy, failing to slow down.

Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

Heavy water is used in nuclear reactor as _________.

  1. Coolant

  2. Moderator

  3. Both coolant and moderator

  4. Catalyst
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Both coolant and moderator.

Heary water ( $D _20$ )  also called deuterium oxide, water composed of deuterium, the hydrogen isotope with a mass double that of ordinary hydrogen and oxygen. The heary water is used as a moderator of neutrons and also as a coolent in nuclear power plants.

Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

How many nuclear power plants does India have in 2018?

  1. 2

  2. 3

  3. 7

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
India has 7 nuclear power plants

India has 22 nuclear reactors in the operation in 7 nuclear power plants, having a total installed capacity of 6780 MW.
List of nuclear power plants
1. Tarapura
operator- NPCIL
Location- Maharashtra
2. Rawatbhata
operator- NPCIL
Location- Rajasthan
3.Kundankulam
operator- NPCIL
Location- Tamil Nadu
4. Kaiga 
operator- NPCIL
Location- Karnataka
5. Kakrapur
operator- NPCIL
Location- Gujrat
6. Kalpakkan
operator- NPCL
Location- Tamil Nadu
7. Narora
operation- NPCIL
Location- Uttar Pradesh
Multiple choice chemistry nuclear physics nuclear reactor the nuclear power station isotopes and nuclear chemistry

What is the importance of moderator in a nuclear reactor?

  1. Moderator controls the flow of water inlet.

  2. Controls the nuclear fission by absorbing the excess neutrons.

  3. Controls the nuclear fission by slowing down the neutrons.

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Controls the nuclear fission by slowing down the neutrons.


A moderator is a material used on a nuclear reactor to slow down the neutrons produced from fission. By slowing down neutrons the probability of a neutron interacting with Uranium-235 nuclei is greatly increased thereby maintaining the chain reaction. Carbon in the form of graphite is commonly used as a moderator.