Question

Among the following statements, which one is wrong?

• A. The energy of thermal neutrons is about $25\text{MeV}$
• B. In a nuclear reactor, when neutrons multiplication factor, $K=1$ then the reaction is said to be critical
• C. ${}_{92}{U}^{235}$undergoes fission by bombardment of high energy neutron
• D. On average $2.5$ neutrons are emitted per fission of ${}_{92}{U}^{235}$
  

Answer 1

The correct option is C ${}_{92}{U}^{235}$undergoes fission by bombardment of high energy neutron

${}_{92}{U}^{235}$undergoes fission by bombardment of thermal neutrons; slow neutrons of energy about $0.025\text{eV}$.

Hence, $\left(C\right)$ is the correct answer.