The positron is

Which of the following is an example of nuclear fission?

Consider an $\alpha$-particle just in contact with a $_{92}U^{238}$ nucleus. Calculate the coulombic repulsion energy (i.e.,the height of the coulombic barrier between $U^{238}$ and $\alpha$-particle) assuming that the distance between them is equal to the sum of their radii.

Uranium ultimately decays into a stable isotope of:

In nuclear reactors,the speed of the neutrons is slowed down by:

Large energy released in an atomic bomb explosion is mainly due to