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If the uncertainties in position and momentum are the same, what is the uncertainty in velocity?

1. 1 / 2m √h / π
2. √h / 2π
3. 1 / m √h / π
4. √h / π

Correct answer: 1 / m √h / π

Solution

From Heisenberg uncertainty principle, 94x94p = h/4c0. If 94x = 94p, then 94p = (h/4c0), and 94v = 94p/m. This gives the required expression.

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