Hydrogen atoms fuse together to form helium atoms. This releases a huge amount of energy in the form of and . (called Nuclear fusion)

Hydrogen atoms fuse together to form helium atoms. This releases a huge amount of energy in the form of Kinetic energy of the alpha particle and Electromagnetic radiation.

Explanation:

Nuclear Fusion is the Nuclear process in which the energy is produced when two lighter elements are collided together which are having some kinetic energy in them after that the two lighter nuclei will fuse together into a single heavier nuclei. This is opposite to what happens in Fission process in which the breaking up of atomic specie happens.

Both Nuclear Fission and Nuclear fission occurs with the release of massive amount of energy.

There are conditions for nuclear fusion to happens like, it requires 100 million's kelvin of temperature, also fusion will occur when the pressure is very high because increased pressure will result into squeezing of the atomic specie and hence they will fuse.

When the Hydrogen atom fuse together to form helium atoms. This release a huge amount of energy in the form of Kinetic energy of the alpha particle and Electromagnetic radiation.