Uncertainty in Speed [ENDORSED]

[Veronica_Lubera_2A]

The hydrogen atom has a radius of approximately 0.05 nm. Assume that we know the position of an electron to an accuracy of 1% of the hydrogen radius, calculate the uncertainty in the speed of the electron using the Heisenberg uncertainty principle.

So the correct answer is Delta V >= 10^8 m/s. How would you solve the question to receive this answer?

[Chem_Mod]

I will be covering this topic in class during Week 2.

Calculate 1% of the hydrogen radius (0.05 nm) in meters and use it as the uncertainty in position, delta x, of the electron in the Heisenberg Indeterminacy (Uncertainty) Equation.

[Sears 4A]

I do not think we are covering this until week 2, and the week 2 homework can be from review or quantum, so maybe wait until Dr. Lavelle goes over this in lecture!

[AnayaArnold_3L]

The hydrogen atom has a radius of approximately 0.05 nm. Assume that we know the position of an electron to an accuracy of 1% of the hydrogen radius, calculate the uncertainty in the speed of the electron using the Heisenberg uncertainty principle.

So the correct answer is Delta V >= 10^8 m/s. How would you solve the question to receive this answer?

Dr.Lavelle will more than likely go over this concept more in a lecture during week 2 so I wouldn't worry about it too much as of right now.

[KatherineValdez_4B]

I really hope he does cover it because I'm confused.

[andrewcj 2C]

I think it goes like this:
(p)(x) = (1/2)(h/2)
(p) = m(v)
From here you can plug in (0.01)*(0.05 nm) for x and solve.

[andrewcj 2C]

One additional thing for my reply, make sure you convert nm to m.

[nicole-2B]

One additional thing for my reply, make sure you convert nm to m.

thanks for clarifying this.

[melinak1]

One additional thing for my reply, make sure you convert nm to m.

ohh ok thank you!

[KatherineValdez_4B]

One additional thing for my reply, make sure you convert nm to m.

Thanks for this I almost forgot to do it.

[Aprice_1J]

Another important conceptual thing to think about is that the more you know about the position of an electron, the less we know about its velocity- they have an inverse relationship.

[Anvi Brahmbhatt 4A]

I think it goes like this:
(p)(x) = (1/2)(h/2)
(p) = m(v)
From here you can plug in (0.01)*(0.05 nm) for x and solve.

Thank you for the explanation!

[Claire Stoecklein 1E]

When you determine delta p for the indeterminacy equation, make sure to use p=mv, using the velocity given in the equation and the mass of electron, 9.109 x 10^-31.

[brennayoung]

This equation can be used for other atoms than hydrogen right?

[Ruth Glauber 1C]

I think you need to calculate 1% of the hydrogen radius (0.05 nm) in meters for the uncertainty.

[Caitlin Ciardelli 3E]

Another way to calc uncertainty in v:

10 ms^-1 +/- .5
You can take the +/- value and multiply it by 2. This is another way to find uncertainty in v

[CMaduno_1L]

In response to Brennayoung's question, I believe that we will only be applying this to hydrogen for now. This principle is used when measuring position and momentum of a particle.

[Sara Richmond 2K]

Use these equations:
(delta p)(delta x) = (1/2)(h/4 PIE)
(deltap) = m( delta v)

Sometimes this type of problem can be confusing because they dont give you the delta p equation.

Also remember to multiply the delta v uncertainty by 2 because it is plus or minus a certain amount.

[Mitchell Koss 4G]

Also, don’t confuse frequency (v) with velocity (v)

[Jack_Pearce_2H]

you would use the heisenberg uncertainty equations to solve this but more likely than not the result would be very off because the electron is known to a very close degree of certainty

[305405193]

If you need more help solving for these uncertainty questions this YouTube video really helped me get through these types of problems here is the link: https://www.youtube.com/watch?v=BNYz5EKXVeI