WEBVTT
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This is College Physics Answers
with Shaun Dychko.
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The uncertainty in the decay energy
of some nuclear state
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is 2 electron volts.
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And so that uncertainty multiplied by
the uncertainty in time
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has to be greater than or equal to
Planck's constant over 4*π*;
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this is the Heisenberg
uncertainty principle.
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And that means that *Δt* then
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after we multiply both sides by
1 over *ΔE* here,
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is Planck's constant over 4*π* times *ΔE*.
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So the minimum uncertainty in time
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is 4.14 times 10 to the minus
15 electron volt seconds
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divided by 4*π* times 2 electron volts
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and this works out to 0.16 femtoseconds,
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is the minimum uncertainty
in the time of this decay.