Question

As per de-broglie formula a microscopic particle of mass $100 g$ and moving at a velocity of $100 cm / sec$ will have a wavelength of:

• A. $6.6 \times 10^{-29} cm / s$
• B. $6.6 \times 10^{-30} cm / s$
• C. $6.6 \times 10^{-31} cm / s$
• D. $6.6 \times 10^{-32} cm / s$

Answer 1

Answer: (C)

According to De-Broglie equation;

Wavelength $(\lambda)=\frac{ h }{ mv }$

Given; $m=100 g, v=100 cm / sec$

$h=6.6 \times 10^{-34} Js =6.6 \times 10^{-27} erg - s$

on substituting values, we get

$\lambda=\frac{6.6 \times 10^{-27}}{100 \times 100}$

$=\frac{6.6 \times 10^{-27}}{10^{4}}$

$=6.6 \times 10^{-31} cm / s$