Question

If an electron having kinetic energy $23V$ is accelerated through the potential difference of $2$ volt. Then calculate the wavelength with the electron.

Answer 1

Kinetic energy of electron=23V

Potential difference = 2V

The total kinetic energy=23+2=25eV

$25\times 1.6\times {10}^{-19}J4\times {10}^{-18}J$

Now by using formula,

$\lambda =\frac{h}{\surd 2mK}$

where, $h=plancksconstant$

$m=massofelectron$

$K=kineticenergy$

therefore,

$\lambda =\frac{6.63\times {10}^{-34}}{\surd 2\times 9.1\times {10}^{-31}\times 6.4\times {10}^{-19}}=6.14\times {10}^{-10}$

=$6.14A^o$

hence debroglie wavelength is $6.14A^o$