## When to double the parameter to get delta v

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

Tinisha 1G
Posts: 69
Joined: Fri Sep 28, 2018 12:17 am

### When to double the parameter to get delta v

In the homework, there are questions that asked for the minimum uncertainty of the object's position, and when it said minimum, the solution's manual did not double the parameter of the velocity. Although, when it does not say minimum, they double the parameter? Does the word "minimum" play a role in whether we double the parameter or not?

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: When to double the parameter to get delta v

Uncertainty in velocity is the difference between the highest and lowest possible values for the velocity. In some cases, velocity is given as a value $\pm$ some error. In this case, you would have to double that error to find the total uncertainty in velocity.

Andrew Sun 1I
Posts: 30
Joined: Fri Sep 28, 2018 12:18 am

### Re: When to double the parameter to get delta v

if a question says the speed is 3.24 +/- 0.06 m/s, would delta V be 0.12 m/s?

Jeremy_Guiman2E
Posts: 82
Joined: Fri Sep 28, 2018 12:29 am

### Re: When to double the parameter to get delta v

Yeah, as Chem Mod said above, "uncertainty in velocity is the difference between the highest and lowest possible values for the velocity".

So given 3.24 +/- 0.06 m/s, our highest possible value is 3.30 and our lowest is 3.18.

The difference of the above values is 0.12 m/s which is what delta v/uncertainty in velocity would be, so yes, it would be 0.12 m/s.