I am a little confused by something by something in my physical chemistry textbook.(adsbygoogle = window.adsbygoogle || []).push({});

If two measurable quantities do not commute, then an uncertainty relation exists for them. Kinetic energy and position do not commute, and the expectation value for linear momentum in a 1-D particle in a box is zero. However, the uncertainty relation for KE and position says that:

Obviously, the uncertainty can't be zero, but I don't see why this equation is correct and I haven't found anything working out the actual integral to reach this result online. Could someone please explain?

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# Uncertainty Principle

Can you offer guidance or do you also need help?

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