Light and Matter

[J89]

1. The problem statement, all variables and given/known data

In the ground state of hydrogen, the uncertainty in the position of the electron is roughly 0.10 nm. If the speed of the electron is approximately the same as the uncertainty in its speed, about how fast is it moving?

2. Relevant equations
h/(4pi*m*v) =
h=6.63e-34
m=9.11e-31
v=.10e-9




3. The attempt at a solution

I thought you should just substitute in everything in the equation...

this is what I'm sure the answer is..but it was marked wrong..

6.63e-34/(4pi*9.11e-31*(.10e-9) = 5.8e5= 1e6..however it is marked wrong..please help!

[zhermes]

velocity does not equal 0.1e-9... you're trying to FIND the velocity. It is just saying that the uncertainty in the velocity is approximately the velocity, i.e.

\Delta v \approx v