Question

Calculate the uncertainty in velocity of a cricket ball of mass $150g$ if the uncertainty in its position is of the order of $1\mathring{A}$ $(h=6.6\times {10}^{-34}kg{m}^2{s}^{-1})$.

Answer 1

$m=150\times {10}^{-3}kg\Delta x={10}^{-10}{A}^0$ h=planck's constant

Using Heisenburg Uncertainity Principle

$\Delta x.m\Delta v\ge \frac{h}{4\pi }\Delta v=\frac{h}{4\pi m\Delta x}\Delta v=\frac{6.626\times {10}^{-34}}{4\times 3.14\times {10}^{-10}\times 0.15}=3.5\times {10}^{-24}{ms}^{-1}$