Estimate the uncertainty in electron's position.

AI Thread Summary
To estimate the uncertainty in an electron's position given its speed range of 6.0×10^6 m/s to 6.7×10^6 m/s, the uncertainty in momentum is calculated using the equation ΔpΔx ≥ h/2π. The attempt at a solution yielded a position uncertainty of approximately 0.00000000016546 m, but this was marked incorrect. Participants in the discussion noted that the velocity range used was appropriate, yet the calculated result did not align with expected answers. The conversation highlights confusion over the accuracy of the calculations and the criteria for correctness in the problem.
Steelers72
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1. Question
The speed of an electron is known to be between 6.0×10^6 m/s and 6.7×10^6 m/s . Estimate the uncertainty in its position.

Homework Equations



ΔpΔx ≥ h/2π
(mΔv) Δx ≥ h/2π (Since Δp= mΔv)

Δx≥ h/2π(mΔv)

h= 6.63*10-34 J*s
c= 3.0*108
mass of electron= 9.11*10-31

The Attempt at a Solution


(6.63*10^-34)/(2pi(9.11*10^-31)*(6.7*10^6 - (6*10^6))
= 0.00000000016546 m

Apparently this is incorrect. What am I doing wrong?
 

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The range of velocities in that picture is different from the one in your problem.
 
blue_leaf77 said:
The range of velocities in that picture is different from the one in your problem.
I am aware, that is why I wrote my work in the 3rd step of the post. I used my own velocity range.
 
Steelers72 said:
Apparently this is incorrect.
Why is it not correct? Using your own velocities, I also got the same value. Do I miss something about what you actually want to figure out?
 
blue_leaf77 said:
Why is it not correct? Using your own velocities, I also got the same value. Do I miss something about what you actually want to figure out?
I'm not sure. My answer was marked incorrect which is strange. I understand the problem and how to do it. I figured maybe my work was wrong or a small error?
 
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