The wavelengths of electron waves in two orbits are in the ratio $3: 5$. The ratio of the kinetic energy of the electrons will be:

Wavelength of $H^{+}$ ion with kinetic energy $1.65 \ eV$ is (mass of proton $= 1.6726 \times 10^{-27} \ kg$) (in $nm$)

The wavelength of an electron is $10^3 \ nm$. What is its momentum (in $kg \ m \ s^{-1}$)? $(h = 6.625 \times 10^{-34} \ J \ s)$

The atomic masses of helium and neon are $4.0$ and $20.0 \ amu$ respectively. The value of the de Broglie wavelength of helium gas at $-73^{\circ} C$ is $M$ times the de Broglie wavelength of neon at $727^{\circ} C$. The value of $M$ is

The mass of an electron is $9.1 \times 10^{-31} \ kg$. If its $K.E.$ is $3.0 \times 10^{-25} \ J$,calculate its wavelength.

If the kinetic energy of a particle is increased to $4$ times its initial value,how many times will the associated de Broglie wavelength become?