The angular momentum of the electron in the third Bohr orbit of a hydrogen atom is $l$. What is its angular momentum in the fourth Bohr orbit?

$A$ $\mu$-meson of charge '$e$',mass $208 m_e$ moves in a circular orbit around a heavy nucleus having charge $+3e$. The quantum state '$n$' for which the radius of the orbit is the same as that of the first Bohr orbit for a hydrogen atom is [approximately]:

If the first excitation potential of a hydrogen-like atom is $V \, \text{volt}$, then the ionization energy of this atom will be

Magnetic moment due to the motion of the electron in the $n$th energy state of a hydrogen atom is proportional to ..........

An electron from various excited states of a hydrogen atom emits radiation to return to the ground state. Let $\lambda_n$ and $\lambda_g$ be the de Broglie wavelength of the electron in the $n^{th}$ state and the ground state,respectively. Let $\Lambda_n$ be the wavelength of the emitted photon in the transition from the $n^{th}$ state to the ground state. For large $n$,which of the following relations holds true ($A, B$ are constants)?

The magnetic moment of an electron due to its orbital motion is proportional to ($n$ = principal quantum number).