Question

The mass of electron is `9.11xx10^(-31)`kg. Calculate the uncertainty in its velocity if the uncertainty in position is the uncertainty in position is of the order of `+-10`pm. `(h=6.6xx10^(-34)"kg"m^(2)s^(-1))`.

Answer 1

Correct Answer - `5.76xx10^(6)m s^(-1)`
According to uncertainty principle, `Deltax.*m delta v=(h)/(4pi) or Deltav=(h)/(4pi m Deltax)`
`h=6.626xx10^(-34) "kg" m^(2)s^(-1), Delta x=10xx10^(-12)m=10^(-11)m, m=9.11xx10^(-31) `kg
`:. " " Deltav=((6.626xx10^(-34)"kg"m^(2)s^(-1)))/(4xx3.143xx(9.11xx10^(-31)"kg")(10^(-11)m))=5.76xx10^(6)ms^(-1)`.