The energy required to remove the electron from a singly ionized Helium atom is 2.2 times the energy required to remove an electron from Helium atom. The total energy required to ionize the Helium atom completely is:

The transition of an electron from ${n_2} = 5,6, \ldots \ldots$ to ${n_1} = 4$ gives rise to

The ratio of longest wavelength and the shortest wavelength observed in the five spectral series of emission spectrum of hydrogen is

Imagine an atom made up of a proton and a hypothetical particle of double the mass of the electron but having the same charge as the electron. Apply the Bohr’s atom model and consider all possible transitions of this hypothetical particle to the first excited level. The longest wavelength photon that will be emitted has wavelength $\lambda$ (given in terms of the Rydberg constant $R$ for the hydrogen atom) is equal to

In Bohr’s model, if the atomic radius of the first orbit is ${r_0}$, then the radius of the fourth orbit is

An electron in a hydrogen atom transitions from an unknown energy level $n_i$ to $n_f = 2$. If the emitted photon has a wavelength of 486 nm, which series does this transition belong to and what is the value of $n_i$? (Rydberg constant, R = $1.097 imes 10^7 m^{-1}$)

Which of the following transition in Balmer series for hydrogen atom will have longest wavelength

The ratio of speed of an electron in ground state in Bohrs first orbit of hydrogen atom to velocity of light in air is

The distance of closest approach of an $\alpha$-particle fired towards a nucleus with momentum $p$, is $r$. If the momentum of the $\alpha$-particle is $2p$, the corresponding distance of closest approach is

In Bohr’s model of hydrogen atom, which of the following represents the variation of nth orbit radius with n?

In terms of Rydberg’s constant $R$, the wave number of the first Balmer line is