Question

What is the wavelength of an electron with a mass of 9.109×10−31 kg and a velocity of 3.43×107 ms? Use 6.626×10−34kg m2s for Planck's constant. Your answer should include three significant figures.

Answer 1

Answer: The wavelength of an electron is $2.121\times 10^{-11}m$

Explanation:

To calculate the wavelength of a particle, we use the equation given by De-Broglie's wavelength, which is:

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

where,

$\lambda$ = De-Broglie's wavelength = ?

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

m = mass of electron = $9.109\times 10^{-31}kg$

v = velocity of electron = $3.43\times 10^{7}m/s$

Putting values in above equation, we get:

$\lambda=\frac{6.626\times 10^{-34}Js}{(9.109\times 10^{-31}kg)\times (3.43\times 10^{7}m/s)}$

$\lambda=2.121\times 10^{-11}m$

Hence, the wavelength of an electron is $2.121\times 10^{-11}m$