In Bohr's model,the atomic radius of the first orbit is $\gamma$. The radius of the $3^{rd}$ orbit is:

The frequency and energy of a photon with a wavelength of $4000 \ \mathring{A}$ are respectively.......

Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying $0.5\, V$ when the radiation of $250\, nm$ is used. The work function of the metal is ................ $eV$

Write the postulates of Bohr's model of the hydrogen atom.

The electron in the hydrogen atom undergoes a transition from higher orbitals to an orbital of radius $211.6 \text{ pm}$. This transition is associated with:

Observe the following statements:
Statement-$I$: Rutherford model of an atom cannot explain the stability of an atom.
Statement-$II$: The wavelength of $X$-rays is higher than the wavelength of microwaves.
The correct answer is: