The energy required (in eV) to excite an electron of H -atom from the ground state to the third state is

The maximum number of electrons present in an orbital with $$n = 4, l = 3$$ is

Which quantum number provides information about the shape of an orbital?

If $$\Delta x$$ is the uncertainty in position and $$\Delta v$$ is the uncertainty in velocity of a particle are equal, the correct expression for uncertainty in momentum for the same particle is