The wavelength of an electron in the first orbit of a hydrogen atom is $3.3 \times 10^{-10} \ m$. The kinetic energy of the electron (in $J$) is:
$(h = 6.6 \times 10^{-34} \ Js, m_{e} = 9.0 \times 10^{-31} \ kg)$

$A$ moving particle may have significant wave motion,if

When light of wavelength $248 \, nm$ falls on a metal of threshold energy $3.0 \, eV$,the de-Broglie wavelength of emitted electrons is ............. $\mathring{A}$ (Round off to the Nearest Integer). [Use : $\sqrt{3}=1.73, h =6.63 \times 10^{-34} \, Js, m_e =9.1 \times 10^{-31} \, kg, c =3.0 \times 10^{8} \, ms^{-1}, 1 \, eV =1.6 \times 10^{-19} \, J$]

What is the de Broglie wavelength of an electron in the $n^{th}$ Bohr orbit?

The de Broglie wavelength of a particle $X$ moving with a certain velocity is $1 \ \mathring{A}$. If the mass of $Y$ is $25\%$ of $X$ and its velocity is $75\%$ of $X$,then the de Broglie wavelength of $Y$ will be ........... $\mathring{A}$.

Calculate the velocity of an electron having a de Broglie wavelength of $58 \ nm$ and mass $9.1 \times 10^{-31} \ kg$. Given: $h = 6.63 \times 10^{-34} \ Js$.