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### Indeterminacy principle

Posted: Tue Jul 09, 2019 11:26 am
12. Heisenberg received the physics Nobel Prize in 1932 for his contributions to quantum mechanics.
What is a qualitative statement of Heisenberg's uncertainty (indeterminacy) principle?
A. There is a limit on the accuracy to which both the size and position of a particle can be known simultaneously.
B. There is a limit on the accuracy to which both the velocity and kinetic energy of a particle can be known simultaneously.
C. There is a limit on the accuracy to which both the momentum and position of a particle can be known simultaneously.
D. There is a limit on the accuracy to which both the momentum and kinetic energy of a particle can be known simultaneously.
E. None of the above

### Re: Indeterminacy principle

Posted: Tue Jul 09, 2019 12:58 pm
Hello,

The best answer is that there is a limit to the accuracy with which both position and momentum can be known. If you look at the equation for Heisenberg’s Uncertainty, you’ll see that the uncertainty in X (position) multiplied by uncertainty in P (momentum) can never be zero, and that the certainty for one of them increases, he certainty in the other decreases. This means arises from the fact that at very small scales, the act of measuring either of these factors has an impact on the result.

### Re: Indeterminacy principle

Posted: Sat Oct 12, 2019 12:48 pm
There is a limit to the accuracy to which both momentum and position are known. In simple terms: it is extremely difficult to pinpoint the exact location of such a minuscule particle while it is moving. Inversely, it is not possible to know the momentum of that particle if it is stopped or slowed to more accurately determine its position.

### Re: Indeterminacy principle

Posted: Sat Oct 12, 2019 1:53 pm
The correct answer is that you can't be certain of the momentum and position of the particle simultaneously. It's basically the idea that by the time you determine the exact position of the particle at an exact time, you no longer have an idea of the momentum of the particle. Likewise, by the time you calculate the momentum of the particle, you can no longer determine exactly where the particle is because you have no idea where the particle started from. (I might be wrong.)