What Is the Minimum Uncertainty in the Length of the Year?

DeltapE >= \hbar/2We can rearrange this to solve for \Deltapx:\Deltapx = \dfrac{\hbar}{2\Deltat\deltapE}6. Substituting this into our equation for \Deltat, we get:\Deltat = -\dfrac{\hbar}{2\Deltat\deltapE} \cdot \dfrac{d\Deltapx}{d\Deltat}7. Now we can solve for \Deltat:\Deltat = \sqrt{\dfrac{\hbar}{2\DeltapE}}In summary, to find the minimum uncertainty in the length of the year, we
  • #1
lyra87
1
0
Sorry for the other post, I clicked post by mistake

Homework Statement


Find the minimum uncertainty in the length of the year

Homework Equations


[tex]\Delta[/tex]Px >= [tex]\hbar[/tex]/(2[tex]\Delta[/tex]x


The Attempt at a Solution


I did:
[tex]\Delta[/tex]t = ((([tex]\Delta[/tex]xt)/x)[tex]^{}2[/tex]+((xm)/[tex]\Delta[/tex]Px)[tex]^{}2[/tex])[tex]^{}.5[/tex]

and then because of the uncertainty principle:
[tex]\Delta[/tex]t =((([tex]\Delta[/tex]xt)/x)[tex]^{}2[/tex]+((2xm[tex]\Delta[/tex]x)/[tex]\hbar[/tex])[tex]^{}2[/tex])[tex]^{}.5[/tex]

then I took the derivative dt/d[tex]\Delta[/tex]x to minimize the function. But [tex]\Delta[/tex]x canceled, and I don't get the correct value for h-bar, so I think I did something wrong.

thanks a lot
 
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Hello, don't worry about the previous post, it happens to all of us! To find the minimum uncertainty in the length of the year, we can use the uncertainty principle, which states that the product of the uncertainties in position and momentum must be greater than or equal to h-bar/2. In this case, we are looking for the uncertainty in time, so we can use the same equation but with time instead of position:

\Deltat\Deltapx >= \hbar/2

To find the minimum uncertainty, we can set the derivative of this equation with respect to \Deltat equal to 0 and solve for \Deltat. This will give us the minimum value for \Deltat, which represents the minimum uncertainty in the length of the year. Let's go through the steps:

1. Take the derivative of \Deltat\Deltapx with respect to \Deltat:

\dfrac{d}{d\Deltat}(\Deltat\Deltapx) = \Deltapx + \Deltat\dfrac{d\Deltapx}{d\Deltat}

2. Set this equal to 0 and solve for \Deltat:

\Deltapx + \Deltat\dfrac{d\Deltapx}{d\Deltat} = 0

\Deltat = -\dfrac{\Deltapx}{\dfrac{d\Deltapx}{d\Deltat}}

3. Now we need to find the derivative \dfrac{d\Deltapx}{d\Deltat}. To do this, we can use the uncertainty principle again, but this time with energy and time:

\Deltat\DeltapE >= \hbar/2

We can rearrange this to solve for \Deltapx:

\Deltapx = \dfrac{\hbar}{2\Deltat\deltapE}

4. Substituting this into our equation for \Deltat, we get:

\Deltat = -\dfrac{\hbar}{2\Deltat\deltapE} \cdot \dfrac{d\Deltapx}{d\Deltat}

5. Now we need to find the derivative \dfrac{d\Deltapx}{d\Deltat}. To do this, we can use the uncertainty principle again, but this time with energy and time:

\Delt
 

FAQ: What Is the Minimum Uncertainty in the Length of the Year?

What is the Heisenberg uncertainty principle?

The Heisenberg uncertainty principle is a fundamental concept in quantum mechanics that states that it is impossible to know both the exact position and momentum of a subatomic particle at the same time. This means that the more precisely we know the position of a particle, the less accurately we can determine its momentum, and vice versa.

Who discovered the Heisenberg uncertainty principle?

The Heisenberg uncertainty principle was discovered by German physicist Werner Heisenberg in 1927. He was awarded the Nobel Prize in Physics in 1932 for his contributions to the development of quantum mechanics.

What is the mathematical representation of the Heisenberg uncertainty principle?

The Heisenberg uncertainty principle can be mathematically represented by the following equation: ΔxΔp ≥ ħ/2, where Δx represents the uncertainty in position, Δp represents the uncertainty in momentum, and ħ is the reduced Planck's constant.

How does the Heisenberg uncertainty principle impact our understanding of the physical world?

The Heisenberg uncertainty principle challenges our traditional understanding of the physical world, which is based on classical mechanics. It shows that at the subatomic level, particles do not have well-defined properties and instead exist in a state of uncertainty. This principle also has practical applications in technologies such as MRI, which relies on the uncertainty principle to produce images.

Is the Heisenberg uncertainty principle absolute or can it be violated?

The Heisenberg uncertainty principle is a fundamental principle in quantum mechanics and is considered to be an absolute law of nature. It has been extensively tested and has not been found to be violated. However, at a macroscopic level, the uncertainty principle is not noticeable due to the large scales and high speeds involved.

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