Determining Uncertainty in Position using Heinsburg's Uncertainty Principle

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aquella7
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Homework Statement



A 52.9 g ball moves at 12.2 m/s.
If its speed is measured to an accuracy of
0.04%, what is the minimum uncertainty in
its position? Answer in units of m.



Homework Equations



delta x times delta p = 1/2 (h/2pi)


The Attempt at a Solution



I used the uncertainty of the speed to determine the minimum and maximum momentums for the ball. I used these to determine what delta p is equal to (0.6195648) and then substituted that number into the equation to solve for delta x. I used kilograms for the mass, which I believe are the correct units as opposed to just grams. If you could help me determine what I am doing wrong, that would be great! Thanks!

Homework Statement

 
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aquella7 said:

Homework Statement



A 52.9 g ball moves at 12.2 m/s.
If its speed is measured to an accuracy of
0.04%, what is the minimum uncertainty in
its position? Answer in units of m.

Homework Equations



delta x times delta p = 1/2 (h/2pi)

The Attempt at a Solution



I used the uncertainty of the speed to determine the minimum and maximum momentums for the ball. I used these to determine what delta p is equal to (0.6195648) and then substituted that number into the equation to solve for delta x. I used kilograms for the mass, which I believe are the correct units as opposed to just grams. If you could help me determine what I am doing wrong, that would be great! Thanks!

Homework Statement


Welcome to PF.

Δp*Δx ≥ ℏ/2

Planck's constant is pretty small, so I'd think you should get a very small number here.

h = 6.6*10−34

And at that you are using ℏ which is h/2π.

Your Δp = .0004*.6344 already, so Δx must be quite small as far as the minimum allowed uncertainty in Δx