## delta V

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

Jonathan Batac - 2D
Posts: 99
Joined: Wed Sep 30, 2020 10:03 pm

### delta V

This may have been answered already, but I just wanted clarification because I am a bit uncertain (hehe :D). If a question gives you +/- (a number) m/s as delta V, do you use that exact number and plug it into the equation or do you multiply it by 2 to account for both the positive and negative values of the number (I don't know if that made much sense). Thank you.

KatarinaReid_3H
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### Re: delta V

Multiply it by 2 because you want the entire spectrum of uncertainty. So either they will tell you exactly what the uncertainty is or if they tell you +/- # then you have to multiply by 2.

ellenulitsky Dis 1I
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### Re: delta V

I was confused by that too! So you multiply it by 2 so that it can be within the entire spectrum of uncertainty, which accounts for the positive or negative uncertainty?

Vivian Chang 3L
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### Re: delta V

ellenulitsky Dis 2E wrote:I was confused by that too! So you multiply it by 2 so that it can be within the entire spectrum of uncertainty, which accounts for the positive or negative uncertainty?

Yup! The plus or minus means the value can range from (i.e. using v = 10 +-5 m, so deltaV= 10m) 5 to 15, which is a 10 m range.

Jiapeng Han 1C
Posts: 85
Joined: Wed Sep 30, 2020 9:50 pm

### Re: delta V

For example, if speed is 10$\pm$3m/s, you could either multiply 3 by 2 or use maximum value to minus the minimum value, that is 13-7=6m/s. Both way is correct.