## Post-Module Question #14

$\Delta p \Delta x\geq \frac{h}{4\pi }$

Karen Ung 2H
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### Post-Module Question #14

Which one of the following statements is correct in describing Heisenberg's uncertainty (indeterminacy) equation?

A. The less precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa.
B. The more precisely the position is determined, the more precisely the momentum is known in this instant, and vice versa.
C. The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa.
D. None of the above

I chose A because I thought the uncertainty of the position and the uncertainty of the momentum multiplied together contributed to the precision of both factors, but A is not the correct answer. Will someone please explain the correct answer?

nathansalce 3e
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Joined: Thu Jul 27, 2017 3:01 am

### Re: Post-Module Question #14

The answer would be C)The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa.

Heisenberg's uncertainty equation involves the concept that the more we know about either position or momentum, the less we know about the other. The way we learn more about position or momentum is shooting a photon at said electron. We use the data from firing the photon at the electron to determine the position or momentum, but the method we use will disturb the other measurement (the one we did not measure for). Thus if we know the absolute position of the electron through methods of light, we cannot know the absolute momentum of said electron. There must be a balance, we cannot know for certain both measurements, the more we know about one measurement, the less we know about the other.

Sabrina Dunbar 1I
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### Re: Post-Module Question #14

In addition to the answer above, by looking at the Heisenberg equation that we have, we see that (deltaP)(deltaX)=h/4pi. deltaP and deltaX are inversely related, meaning that as one value increases, the other value decreases.