Question

A body of mass $10\, mg$ is moving with a velocity of $100\, ms^{-1}$ . The wavelength of de-Broglie wave associated with it would be
(Note : $h = 6.63 \times 10^{-34}Js)$

• A. $6.63 \times 10^{-37}m$
• B. $6.63 \times 10^{-31}m$
• C. $6.63 \times 10^{-34}m$
• D. $6.63\times10^{-35}$

Answer 1

Answer: (B)

$m = 10\,mg = 10 \times10^{-6}\, kg$

$ v = 100 ms^{-1} $

$ \lambda = \frac{h}{mv} = \frac{6.63 \times10^{-34}}{10 \times10^{-6} \times100} $

$ = 6.63 \times10^{-31} \,m $