Q25 / 180 · KCET 2007 · Chemistry
A body of mass $10 \mathrm{mg}$ is moving with a velocity of $100 \mathrm{~ms}^{-1}$. The wavelength of de-Broglie wave associated with it would be ( $h=6.63 \times 10^{-34} \mathrm{Js}$ )
- A$6.63 \times 10^{-35} \mathrm{~m}$
- B$6.63 \times 10^{-34} \mathrm{~m}$
- Correct answerC$6.63 \times 10^{-31} \mathrm{~m}$
- D$6.63 \times 10^{-37} \mathrm{~m}$
Solution
$m=10 \mathrm{mg}=10 \times 10^{-6} \mathrm{~kg}$
$$
\begin{aligned}
v &=100 \mathrm{~ms}^{-1} \\
\lambda &=\frac{h}{m v}=\frac{6.63 \times 10^{-34}}{10 \times 10^{-6} \times 100} \\
&=6.63 \times 10^{-31} \mathrm{~m}
\end{aligned}
$$
Hence, the correct answer is option: 'C'.