Question

What will be the wavelength of an electron moving with $\frac{1}{10}th$ of velocity of light?

• A. $2.43\times 10^{-11}m$
• B. $243\times 10^{-11}m$
• C. $0.243m$
• D. $2.43\times 10^{-4}m$

Answer 1

Answer: (A)

$v=\frac{3\times 10^8}{10}=3\times 10^{7}m{s}^{-1}$
$\lambda =\frac{h}{mv}=\frac{6.626\times 10^{-34}Js}{9.1\times 10^{-31}kg\times 3\times 10^{7}m{s}^{-1}}$
$=2.43\times 10^{-11}m$