## Units

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

Henry Krasner 1C
Posts: 64
Joined: Fri Sep 28, 2018 12:15 am

### Units

What units are used in the Heisenberg Equation? Especially for indeterminacy in position?

Jessica Chen 1F
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

### Re: Units

deltap x deltax >= h/4pi

p (momentum) - kg x m/s
x (position) - m

Megan Gianna Uy 3L
Posts: 30
Joined: Fri Sep 28, 2018 12:26 am

### Re: Units

The Heisenberg Uncertainty Equation is deltap x delta x = h/4pi,
where deltap =m x deltav

m= mass (kilograms)
deltav = distance(meters)/time(second)
deltax = distance(meters)
h= planck's constant (kg x m^2/s)

Karan Thaker 2L
Posts: 75
Joined: Fri Sep 28, 2018 12:26 am

### Re: Units

also important to note that the Plancks constant and momentum units are a bit odd, but they always work themselves out by cancelling, especially when we solve for indeterminacy in position. may be worth practicing working through the units and looking at how they cancel out, because this becomes really convoluted sometimes and we can lose points on a test for errors in units.

305154707
Posts: 31
Joined: Fri Sep 28, 2018 12:16 am

### Re: Units

It helps me to memorize the units of Planck's constant/J (kgm^2^s^2) since I know that anything I enter into the equation from there will either have to be of these units or converted to them so I can cancel out. So mass would be in kg and velocity would be in m/s.

Alan Chang
Posts: 33
Joined: Fri Sep 28, 2018 12:29 am

### Re: Units

Is it better to always change the units into the standard units used in the equation before calculations are done?

Rebecca Park
Posts: 30
Joined: Fri Sep 28, 2018 12:17 am

### Re: Units

I've always changed it

Jennifer Lathrop 1F
Posts: 71
Joined: Sat Dec 02, 2017 3:00 am

### Re: Units

How do the units in the equation cancel out? What units are you left with after the equation has been completed?

Maharsh Patel 4E
Posts: 18
Joined: Fri Sep 28, 2018 12:27 am

### Re: Units

The units that you end with depend on what value you are solving for. If you are trying to find ∆x, it would be meters. If you are looking for ∆p, it would kg•m/s.