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.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
The kinetic energy $(K.E.)$ is given by the formula: $K.E. = \frac{1}{2}mv^2$.
First,calculate the velocity $(v)$:
$v = \sqrt{\frac{2 \times K.E.}{m}} = \sqrt{\frac{2 \times 3.0 \times 10^{-25} \ J}{9.1 \times 10^{-31} \ kg}} \approx 812 \ m \ s^{-1}$.
Now,use the de Broglie wavelength formula: $\lambda = \frac{h}{mv}$.
Substituting the values: $\lambda = \frac{6.626 \times 10^{-34} \ J \ s}{(9.1 \times 10^{-31} \ kg) \times (812 \ m \ s^{-1})}$.
$\lambda \approx 8.967 \times 10^{-7} \ m = 896.7 \ nm$.

Explore More

Similar Questions

Calculate the de-Broglie wavelength of an electron travelling at $1\%$ of the speed of light.

Difficult
View Solution

$A$ 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 $Li^{3+} = 8.3 \times \text{mass of proton}$)

What should be the ratio of velocities of $CH_4$ and $O_2$ molecules so that they are associated with de Broglie waves of equal wavelength?

Difficult
View Solution

The condition for a stable wave in an orbit of radius $r$ is given by the de Broglie relationship where the circumference of the orbit must be an integral multiple of the wavelength.

Calculate the $\lambda$ of $CO_2$ molecule moving with a velocity $440 \ m/s.$

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo