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supermenscher
Aug5-04, 10:26 AM
A proton is traveling with a speed of (6.550+/- 0.010)e5 m/s. With what maximum accuracy can its position be ascertained.

I know that p=mv and x=p/h but what do I do with the +/- 0.010, that is the part that confuses me.

How many electrons can be in the n=6, l=4 subshell. I know that l is n-1, so that can be 5, and n=6, so can the atom have 5 electrons?

Tom Mattson
Aug5-04, 02:36 PM
I know that p=mv and x=p/h but what do I do with the +/- 0.010, that is the part that confuses me.


That's the uncertainty in the velocity.


How many electrons can be in the n=6, l=4 subshell. I know that l is n-1, so that can be 5, and n=6, so can the atom have 5 electrons?

No. n is not the number of electrons in a shell, it's the energy level. You need to list out the quantum states and count them.

supermenscher
Aug5-04, 02:43 PM
Yes I know that 0.010 is the uncertainity of the velcoity, but how do I incorporate that into the equation?

Tom Mattson
Aug5-04, 03:16 PM
Yes I know that 0.010 is the uncertainity of the velcoity, but how do I incorporate that into the equation?

Sorry, but I'm not answering that one directly. You should be reading the book.

Now think: What principle in quantum mechanics expresses a mathematical relationship between uncertainty in momentum and uncertainty in position?

Gokul43201
Aug5-04, 04:38 PM
x = p/h ? Not true ! Reread the part about the Uncertainty Principle.

For a given value of 'l', how many values can 'm' take ? For each of these 'm', how many values of 's' can there be ?