An `H` atom in ground state is moving with initial kinetic energy `K` .It collides head on with `He ^(+)` ion in ground state kept at rest but free to move. Find minimum value of `K` so that both the particles can excite to their first excited state.

A He^(+) ion is at rest and is in ground state. A necutron with intial kinetic energy K collides heads on with the He^(+) ion. Find minimum value of K so that there can be an inelastic collision between these two particals.

A He^(+) ion is at rest and is in ground state. A necutron with intial kinetic energy K collides heads on with the He^(+) ion. Find minimum value of K so that there can be an inelastic collision between these two particals.

A free hydrogen atom in its ground state is at rest. A neutron having kinetic energy k_(0) collides head one with the atom. Assume that mass of both neutron and the atom is same. (a) Find minimum value of k_(0) so that this collision can be inelastic. (b) If k_(0) = 25 eV , find the kinetic energy of neutron after collision if its excites the hydrogen atom to its second excited state. Take ionization energy of hydrogen atom in ground state to be 13.6 eV .

The ratio of energies of first excited state of He^+ ion and ground state of H^− atom is

When a hydrogen atom is excited from ground state to first excited state then

When a hydrogen atom is excited from ground state to first excited state then

When a hydrogen atom is excited from ground state to first excited state then