The energy required to release $1$ electron from $He^{+}$ is $............$ $eV$.

The ratio of the velocity of an electron in the second orbit of $He^{+}$ to the third orbit of $B^{4+}$ is:

The electron present in an excited state of $He^{+}$ ion shows separation (ionization) on collision with an electron having $2.5 \ eV$ energy. What will be the minimum value of $n$ for this electron of $He^{+}$ ion?

In Bohr's model of an atom,when an electron jumps from $n = 1$ to $n = 3$,how much energy is absorbed?

When an electron makes a transition from $(n+1)$ state to $n^{th}$ state,the frequency of emitted radiation is related to $n$ according to $(n >> 1)$:

Which electron transition in a hydrogen atom requires the largest amount of energy?