The energy of an electron in the first Bohr orbit of the H-atom is -13.6 eV.

The magnitude of energy value of an electron in the first excited state of Be³⁺ is ________ eV (nearest integer value).

Based on Heisenberg's uncertainty principle, the uncertainty in the velocity of the electron to be found within an atomic nucleus of diameter $$10^{-15} \mathrm{~m}$$ is ________ $$\times 10^9 \mathrm{~ms}^{-1}$$ (nearest integer)

[Given : mass of electron $$=9.1 \times 10^{-31} \mathrm{~kg}$$, Plank's constant $$(h)=6.626 \times 10^{-34} \mathrm{Js}$$] (Value of $$\pi=3.14$$)

Wavenumber for a radiation having 5800 $$\mathop A\limits^o $$ wavelength is $$x \times 10 \mathrm{~cm}^{-1}$$ The value of $$x$$ is ________. (Integer answer)

A hypothetical electromagnetic wave is show below.

The frequency of the wave is $$\mathrm{x} \times 10^{19} \mathrm{~Hz}$$.

$$\mathrm{x}=$$ _________ (nearest integer)