$A$ ball weighing $25 \ g$ moves with a velocity of $6.6 \times 10^4 \ cm/sec$. Find the associated de Broglie wavelength.

How fast is an electron moving if it has a wavelength equal to the distance it travels in one second?

Which of the following expressions represents the de-Broglie relationship?

$A$ proton and a $Li^{3+}$ nucleus are accelerated by the same potential. If $\lambda_{Li}$ and $\lambda_{P}$ denote the de Broglie wavelengths of $Li^{3+}$ and proton respectively,then the value of $\frac{\lambda_{Li}}{\lambda_{P}}$ is $x \times 10^{-1}$. The value of $x$ is ............
(Rounded off to the nearest integer)
(Mass of $Li^{3+} = 8.3 \times \text{mass of proton}$)

If $a_0$ is the Bohr radius,then the de-Broglie wavelength of an electron revolving in the second excited state of the $H$ atom will be:

The wavelength (in $m$) of a particle of mass $11.043 \times 10^{-26} \ kg$ moving with a velocity of $6.0 \times 10^7 \ ms^{-1}$ is $.......$