The nucleus of $_6C^{12}$ absorbs a neutron and emits a $\beta$-particle. The resulting nucleus is ........

The minimum kinetic energy needed by an alpha particle to cause the nuclear reaction ${ }_{7}^{16} N +{ }_{2}^{4} He \rightarrow{ }_{1}^{1} H +{ }_{8}^{19} O$ in a laboratory frame is $n$ (in $MeV$). Assume that ${ }_{7}^{16} N$ is at rest in the laboratory frame. The masses of ${ }_{7}^{16} N, { }_{2}^{4} He, { }_{1}^{1} H$ and ${ }_{8}^{19} O$ can be taken to be $16.006 \ u, 4.003 \ u, 1.008 \ u$ and $19.003 \ u$,respectively,where $1 \ u = 930 \ MeV/c^2$. The value of $n$ is. . . . .

If $200 \text{ MeV}$ of energy is released in the fission of one nucleus of ${ }_{92}^{236} U$, the number of nuclei that must undergo fission to release an energy of $1000 \text{ J}$ is

The function of a moderator in a nuclear reactor is:

Match the $\text{LIST-I}$ with $\text{LIST-II}$:

$A. \text{ } _0^1 n + { }_{92}^{235} U \rightarrow { }_{54}^{140} Xe + { }_{38}^{94} Sr + 2_0^1 n$	$I. \text{ Chemical reaction}$
$B. \text{ } 2H_2 + O_2 \rightarrow 2H_2O$	$II. \text{ Fusion with } +ve \ Q \text{ value}$
$C. \text{ } _1^2 H + _1^2 H \rightarrow _2^3 He + _0^1 n$	$III. \text{ Fission}$
$D. \text{ } _1^1 H + _1^3 H \rightarrow _1^2 H + _1^2 H$	$IV. \text{ Fusion with } -ve \ Q \text{ value}$

Choose the correct answer from the options given below:

The solar energy is primarily due to: