Question

As per de Broglie’s formula a macroscopic particle of mass $100 \,gm$ and moving at a velocity of $100\, cm \,s^{-1}$ will have a wavelength of

• A. $6.6 × 10^{-29}\, cm$
• B. $6.6 × 10^{-30}\, cm$
• C. $6.6 × 10^{-31}\, cm$
• D. $6.6 × 10^{-32}\, cm$

Answer 1

Answer: (C)

According to de-Broglie, wavelength, $\lambda=\frac{h}{m v}$
Given, $m=100\, g , v =100\, cm \,s ^{-1}$
and $h =6.6 \times 10^{-34} \,J - s $
$=6.6 \times 10^{-27} \,erg - s$
On substituting values, we get
$\lambda=\frac{6.6 \times 10^{-27}}{100 \times 100}$
$=6.6 \times 10^{-31} \,cm$