Find the value of $x$ and $y$ in the following nuclear reaction:
${}_{92}^{235} U + {}_{0}^{1} n \rightarrow {}_{x}^{133} Sb + {}_{41}^{y} Nb + 4 {}_{0}^{1} n$

In the proton-proton cycle in the Sun,the energy released when an electron and its antiparticle combine is $\qquad$ .

When $^{235}_{92}U$ is bombarded with one neutron,fission occurs and the products are three neutrons,$^{94}_{36}Kr$ and:

The example of nuclear fusion is

Mention the use of controlled nuclear fission. Mention the use of uncontrolled nuclear fission.

The electrostatic energy of a nucleus of charge $Ze$ is equal to $\frac{k Z^2 e^2}{R}$,where $k$ is a constant and $R$ is the nuclear radius. The nucleus divides into two daughter nuclei of charges $\frac{Ze}{2}$ and equal radii. The change in electrostatic energy in the process when they are far apart is