Question

An object has a mass of 6 kg and velocity of 10 m/s. The speed is measured with 5% accuracy, then find out Δx in m.

(a) 0.12676 x 10^-34

(b) 0.1566 x 10^-34

(c) 0.176 x 10^-34

(d) 0.276 x 10^-34

This question was addressed to me during an interview.

I would like to ask this question from Towards Quantum Mechanical Model of the Atom in division Structure of Atom of Chemistry – Class 11

Answer 1

The correct choice is (c) 0.176 x 10^-34

To elaborate: Speed’s uncertainty is 10 x 5/100 = 0.5 m/s. We have Heisenberg’s principle of uncertainty i.e. Δx. Δp ≥ h/4π. Δx = h/2mπ. Therefore uncertainty in position = 6.626 x 10^-34 Js/12 x 3.1416 = 0.176 x 10^-34.