The de-Broglie wavelength of an electron moving with a velocity of $1.5 \times 10^8 \mathrm{~m} /…
The de-Broglie wavelength of an electron moving with a velocity of $1.5 \times 10^8 \mathrm{~m} / \mathrm{s}$ is equal to that of a photon. The ratio of kinetic energy of the electron to that of the photon $\left(c=3 \times 10^8 \mathrm{~m} / \mathrm{s}\right)$
$2$
$4$
$\frac{1}{2}$
$\frac{1}{4}$
Solution
The ratio of kinetic energy of the electron to that of the photon.
$\begin{aligned} & =\frac{v}{2 c} \\ & =\frac{1.5 \times 10^8}{2 \times 3 \times 10^8}=\frac{1}{4}\end{aligned}$