Question

Uncertainity in position of a particle of 25 g in space is ${10}^{-15}$ m. Determine uncertainity in velocity (m $se{c}^{-1}$) in it. (plank's constant, $h=6.6\times {10}^{-34}$ Js)

• A. $2.1\times {10}^{-18}$
• B. $1.2\times {10}^{-18}$
• C. $1.8\times {10}^{-18}$
• D. $2.5\times {10}^{-18}$

Answer 1

The correct option is A $2.1\times {10}^{-18}$

The uncertainty in velocity, $\Delta v$ is given by the expression:
$\Delta x=\frac{h}{n\pi }\frac{1}{m\Delta v}$.

$=\frac{6.63\times {10}^{-34}Js}{4\times 3.14\times 25\times {10}^{-3}kg\times {10}^{-5}m}$

$=2.1\times {10}^{-28}{s}^{-1}$