Question

33. An electron has a mass 9.108x10-3'kg and
velocity 0.6x109 ms'. Calculate the
wavelength of the electron.​

Answer 1

Answer : The wavelength of electron is $1.2\times 10^{-12}m$

Explanation :

According to de-Broglie, the expression for wavelength is,

$\lambda=\frac{h}{p}$

and,

$p=mv$

where,  

p = momentum, m = mass, v = velocity

So, the formula will be:

$\lambda=\frac{h}{mv}$

where,

h = Planck's constant = $6.626\times 10^{-34}Js$

$\lambda$ = wavelength  = ?

m = mass   of electron = $9.108\times 10^{-31}kg$

v = velocity = $0.6\times 10^9m/s$

Now put all the given values in the above formula, we get:

$\lambda=\frac{h}{mv}$

$\lambda=\frac{6.626\times 10^{-34}Js}{(9.108\times 10^{-31}kg)\times (0.6\times 10^9m/s)}$

$\lambda=1.2\times 10^{-12}m$

Therefore, the wavelength of electron is $1.2\times 10^{-12}m$