Question

A body of mass $100g$ moves at the speed of $36km/h$. The de-Broglie wavelength related to it is of the order _________ $m$.
$(h=6.626\times {10}^{-34}Js)$

• A. ${10}^{-24}$
• B. ${10}^{-14}$
• C. ${10}^{-34}$
• D. ${10}^{-44}$

Answer 1

The correct option is C ${10}^{-34}$

Given, $m=100g=0.1kg$
$v=36km/h=36\times \frac{5}{18}m/s=2\times 5=10m/s$
$h=6.626\times {10}^{-34}Js$
We know that
$\lambda =\frac{h}{mv}$ $(\because p=\frac{h}{\lambda }andp=mv)$
$=\frac{6.626\times {10}^{-34}}{0.1\times 10}$
$\lambda =6.626\times {10}^{-34}m$
So, the de-Broglie wavelength related to it is of the order ${10}^{-34}m$