## 1B.27

$\Delta p \Delta x\geq \frac{h}{4\pi }$

Jayden_Yamasaki_2J
Posts: 50
Joined: Wed Sep 30, 2020 10:03 pm

### 1B.27

Hello! For this problem people have said that the answer in the book is wrong and that the delta v value should be 10 instead of 5, but I still don't understand why you would use 10 since it is asking for the minimum. If someone could help me out I'd really appreciate it thanks! Here's the problem:

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?

Natalie Do 3F
Posts: 109
Joined: Wed Sep 30, 2020 10:03 pm

### Re: 1B.27

You use ten because the speed can be between 0 and 10 meters per second. It can be 5-5m/s or 5+10m/s or anything in between. Therefore, your delta p is 8x10.

Rose_Malki_3G
Posts: 123
Joined: Wed Sep 30, 2020 10:02 pm

### Re: 1B.27

The speed can be between 0m/s and 10m/s therefore the uncertainty in the speed is 10m/s (not 5)

Rose_Malki_3G
Posts: 123
Joined: Wed Sep 30, 2020 10:02 pm

### Re: 1B.27

The speed can be between 0m/s and 10m/s therefore the uncertainty in the speed is 10m/s (not 5)

Mikayla James 2A
Posts: 90
Joined: Wed Sep 30, 2020 9:31 pm
Been upvoted: 2 times

### Re: 1B.27

The "+/- 5.0 m/s" part of the question that describes the velocity indicates the spread of the possible velocities around 5 m/s. This spread of velocity means that the velocity is "uncertain" because it can be anywhere from 0 to 10 m/s and therefore, the uncertainty in velocity is delta 10 m/s.

Jayden_Yamasaki_2J
Posts: 50
Joined: Wed Sep 30, 2020 10:03 pm

### Re: 1B.27

Thanks everyone for the help! Just to clarify, even though the question asks for the minimum uncertainty you would still use 10 because delta v=10?