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)

$v=\frac{3 \times 1 0^{8}}{10}=3\times 10^{7}ms^{- 1}$
$\lambda =\frac{h}{m v}=\frac{6.626 \times 1 0^{- 34} J s}{9.1 \times 1 0^{- 31} k g \times 3 \times 1 0^{7} m s^{- 1}}$
$=2.43\times 10^{- 11}m$