Diameter specified as delta x

[abdhi jadeja [2A]]

Are we expected to make the assumption that if a question regarding velocity u certainty gives us an atom’s diameter, that diameter corresponds to the delta x value?

[Hao Tam Tran 3H]

Hi!

Yes, this is the assumption we make. Think about it this way: delta x refers to the uncertainty in position, so if we're looking at an electron, we aren't sure where in the atom that electron is located. However, what we do know is that the electron will be inside the diameter of the atom, so that is as far as our certainty in position can go. Consequently, that will be our delta x. Hope that helps!

[Brandon Ignacio 2J]

Hi, as the previous person stated, this is pretty much the case anytime the diameter is given in an uncertainty problem. Additionally, at one of the UA sessions I went to, he talked about how sometimes the problem will give the radius or state that it is "confined to an atom" in which case you would end up multiplying by two to get the uncertainty in postion.