Heisenberg's uncertainty principle
Δx×Δpx≥4πh
⇒2a0×mΔvx=4πh(minimum)
⇒Δvx=4πh×2a01×m1
=4×3.14×2×52.9×10−12×9.1×10−316.63×10−34
=548273ms−1
=548.273kms−1
=548kms−1
The minimum uncertainty in the speed of an electron in one dimensional region of length 2ao
(Where ao= Bohr radius 52.9pm) is____kms−1 (Nearest integer) (Given : Mass of electron =9.1×10−31kg, Planck's constant h=6.63×10−34Js)
Held on 29 Jul 2022 · Verified 6 Jul 2026.
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