## 1 B27

Jarrett Peyrefitte 2K
Posts: 102
Joined: Sat Aug 24, 2019 12:16 am

### 1 B27

I am confused on where to start for this problem. What are the steps to find the minimum uncertainty? What do i do with the given numbers?

"A bowling ball of mass 8.00 kg is rolled down a bowling alley lane at 5.00 ± 5.0 m.s?" What is the minimum uncertainty in its position?"

Alexis Webb 2B
Posts: 124
Joined: Thu Jul 11, 2019 12:15 am

### Re: 1 B27

You need to use the Heisenberg Uncertainty Principle which is delta p times delta x is greater than or equal to Plancks constant divided by 4 pi. The problem gives you the delta p (uncertainty in momentum) which is 5.0m/s. Now you wanna solve for delta x (uncertainty in position). So Delta X= h/(4pi)(delta p). This should lead you to the answer.

Ashley Nguyen 2L
Posts: 103
Joined: Sat Aug 17, 2019 12:18 am
Been upvoted: 1 time

### Re: 1 B27

On this problem, you are given the mass and uncertainty in velocity. You can use these numbers to solve for the uncertainty in momentum using the equation p = mv. You can then use this calculated value of p in the Heisenberg Uncertainty Principle, which is defined as deltaP*deltaX >= h / (4pi). Rearrange the equation as deltaX >= h / (4pi(deltaP)) to get the uncertainty in position.

Emma Popescu 1L
Posts: 105
Joined: Wed Sep 11, 2019 12:16 am

### Re: 1 B27

I am confused as to why we use 5 as the uncertainty in velocity. Aren't we suppose to use 10 as it is +-5m/s?

Charlene Datu 2E
Posts: 62
Joined: Wed Sep 11, 2019 12:16 am

### Re: 1 B27

Yes we're supposed to use 10m/s as our uncertainty in velocity. I think it was just a little fumble in the other explanation. It's also good to know that the equation to use, to be more precise, is Δp=mΔv (just in case that might've confused someone)

Sara Richmond 2K
Posts: 110
Joined: Fri Aug 30, 2019 12:16 am

### Re: 1 B27

I am so confused by this problem. I have included two photos. One of my work and one of the solution guide's work. Where did the solution guide get the equation they used? What is wrong with the equations I used?
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