Question

The energy released per fission of ${ }_{92} U^{235}$ is 200 Mev. The fission rate of ${ }_{92} U^{235}$
required to produce 2-watt power is
(A) $1.25 \times 10^{26}$ per second
(B) $2.56 \times 10^{26}$ per second
(C) $1.25\times {{10}^{13}}\text{ per second }$
(D) $6.25\times {{10}^{10}}\text{per second}$

Answer 1

Hint: It should be known to us that fundamental force, also called fundamental interaction, in physics, any of the four basic forces gravitational, electromagnetic, strong, and weak that govern how objects or particles interact and how certain particles decay. All the known forces of nature can be traced to these fundamental forces. The strong nuclear force, also called the strong nuclear interaction, is the strongest of the four fundamental forces of nature. Weight is a force acting on that matter. Mass resists any change in the motion of objects. In physics, the term weight has a specific meaning - which is the force that acts on a mass due to gravity. Weight is measured in newtons. Based on this concept we have to solve this question.

Complete step by step answer We know that,
1 fission causes $200 \mathrm{MeV}$.
$1 \mathrm{MeV}=1.6 \times 10^{-13} \mathrm{J}$
i.e. $200 \mathrm{MeV}=3.2 \times 10^{-11} \mathrm{J}$
To generate $2 \mathrm{W},$ we need $\dfrac{2}{3.2 \times 10^{-11}}$ fission every second.
$=6.25 \times 10^{10}$ fissions per second.

Therefore, the correct answer is Option D.

Note: We can conclude that in nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into two or more smaller, lighter nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactive decay. Nuclear fission, subdivision of a heavy atomic nucleus, such as that of uranium or plutonium, into two fragments of roughly equal mass. The process is accompanied by the release of a large amount of energy. In nuclear fission the nucleus of an atom breaks up into two lighter nuclei.